{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T18:48:00Z","timestamp":1790794080903,"version":"4.1.0"},"reference-count":59,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2017,3,9]],"date-time":"2017-03-09T00:00:00Z","timestamp":1489017600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41501385"],"award-info":[{"award-number":["41501385"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41471306"],"award-info":[{"award-number":["41471306"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"GF4 Project","award":["30-Y20A02-9003-15\/16"],"award-info":[{"award-number":["30-Y20A02-9003-15\/16"]}]},{"name":"German Research Foundation","award":["40101199"],"award-info":[{"award-number":["40101199"]}]},{"name":"German Research Foundation","award":["40101200"],"award-info":[{"award-number":["40101200"]}]},{"DOI":"10.13039\/501100000844","name":"European Space Agency","doi-asserted-by":"publisher","award":["40101124"],"award-info":[{"award-number":["40101124"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The recently launched Chinese GaoFen-4 (GF4) satellite provides valuable information to obtain geophysical parameters describing conditions in the atmosphere and at the Earth\u2019s surface. The surface reflectance is an important parameter for the estimation of other remote sensing parameters linked to the eco-environment, atmosphere environment and energy balance. One of the key issues to achieve atmospheric corrected surface reflectance is to precisely retrieve the aerosol optical properties, especially Aerosol Optical Depth (AOD). The retrieval of AOD and corresponding atmospheric correction procedure normally use the full radiative transfer calculation or Look-Up-Table (LUT) methods, which is very time-consuming. In this paper, a Simplified AtmospHeric correction AlgoRithm for gAofen data (SAHARA) is presented for the retrieval of AOD and corresponding atmospheric correction procedure. This paper is the first part of the algorithm, which describes the aerosol retrieval algorithm. In order to achieve high-accuracy analytical form for both LUT and surface parameterization, the MODIS Dark-Target (DT) aerosol types and Deep Blue (DB) similar surface parameterization have been proposed for GF4 data. Limited Gaofen observations (i.e., all that were available) have been tested and validated. The retrieval results agree quite well with MODIS Collection 6.0 aerosol product, with a correlation coefficient of R2 = 0.72. The comparison between GF4 derived AOD and Aerosol Robotic Network (AERONET) observations has a correlation coefficient of R2 = 0.86. The algorithm, after comprehensive validation, can be used as an operational running algorithm for creating aerosol product from the Chinese GF4 satellite.<\/jats:p>","DOI":"10.3390\/rs9030253","type":"journal-article","created":{"date-parts":[[2017,3,9]],"date-time":"2017-03-09T11:12:17Z","timestamp":1489057937000},"page":"253","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["SAHARA: A Simplified AtmospHeric Correction AlgoRithm for Chinese gAofen Data: 1. Aerosol Algorithm"],"prefix":"10.3390","volume":"9","author":[{"given":"Lu","family":"She","sequence":"first","affiliation":[{"name":"The Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Linlu","family":"Mei","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"Institute of Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong","family":"Xue","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"Department of Electronics, Computing and Mathematics, College of Engineering and Technology, University of Derby, Kedleston Road, Derby DE22 1GB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yahui","family":"Che","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Guang","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,3,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1593","DOI":"10.5194\/amt-8-1593-2015","article-title":"The impact of the microphysical properties of aerosol on the atmospheric correction of hyperspectral data in coastal waters","volume":"8","author":"Bassani","year":"2015","journal-title":"Atmos. Meas. Tech."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"8391","DOI":"10.3390\/rs70708391","article-title":"Effect of the Aerosol Model Assumption on the Atmospheric Correction over Land: Case Studies with CHRIS\/PROBA Hyperspectral Images over Benelux","volume":"7","author":"Tirelli","year":"2015","journal-title":"Remote Sens."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"L08805","DOI":"10.1029\/2007GL029253","article-title":"On the twilight zone between clouds and aerosols","volume":"34","author":"Koren","year":"2007","journal-title":"Geophys. Res. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Mei, L., Vountas, M., Gomez-Chova, L., Rozanov, V., Jager, M., Lotz, W., Burrows, J.P., and Hollmann, R. (2016). A Cloud masking algorithm for the XBAER aerosol retrieval using MERIS data. Remote Sens. Environ.","DOI":"10.1016\/j.rse.2016.11.016"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2989","DOI":"10.5194\/amt-6-2989-2013","article-title":"The Collection 6 MODIS aerosol products over land and ocean","volume":"6","author":"Levy","year":"2013","journal-title":"Atmos. Meas. Tech."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"9296","DOI":"10.1002\/jgrd.50712","article-title":"Enhanced DB aerosol retrieval algorithm: The second generation","volume":"118","author":"Hsu","year":"2013","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.rse.2013.04.014","article-title":"A Simplified high resolution MODIS Aerosol Retrieval Algorithm (SARA) for use over mixed surfaces","volume":"136","author":"Bilal","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"9167","DOI":"10.5194\/acp-12-9167-2012","article-title":"Retrieval of aerosol optical depth over land based on a time series technique using MSG\/SEVIRI data","volume":"12","author":"Mei","year":"2012","journal-title":"Atmos. Chem. Phys."},{"key":"ref_9","first-page":"D03211","article-title":"Multiangle implementation of atmospheric correction (MAIAC): 2. Aerosol algorithm","volume":"116","author":"Lyapustin","year":"2011","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Kokhanovsky, A.A., and de Leeuw, G. (2009). Satellite Aerosol Remote Sensing over Land, Praxis Publishing. [1st ed.].","DOI":"10.1007\/978-3-540-69397-0"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.atmosres.2011.03.006","article-title":"Fast retrieval of aerosol optical depth and its sensitivity to surface albedo using remote sensing data","volume":"116","author":"Seidel","year":"2012","journal-title":"Atmos. Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"17051","DOI":"10.1029\/96JD03988","article-title":"Operational remote sensing of tropospheric aerosol over land from EOS moderate resolution imaging spectral radiometer","volume":"102","author":"Kaufman","year":"1997","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_13","unstructured":"Chandrasekhar, S. (1960). Raditive Transfer, Oxford University Press. [1st ed.]."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"31865","DOI":"10.1029\/98JD00399","article-title":"Measurements of irradiance attenuation and estimation of aerosol single scattering albedo for biomass burning aerosols in Amazonia","volume":"103","author":"Eck","year":"1998","journal-title":"J. Geophys. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3425","DOI":"10.1029\/2000JD900555","article-title":"Characterization of the optical properties of biomass burning aerosols in Zambia during the 1997 ZIBBEE field campaign","volume":"106","author":"Eck","year":"2001","journal-title":"J. Geophys. Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"590","DOI":"10.1175\/1520-0469(2002)059<0590:VOAAOP>2.0.CO;2","article-title":"Variability of absorption and optical properties of key aerosol types observed in worldwide locations","volume":"59","author":"Dubovik","year":"2002","journal-title":"J. Atmos. Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"6831","DOI":"10.1029\/96JD03436","article-title":"Radiative forcing and climate response","volume":"102","author":"Hansen","year":"1997","journal-title":"J. Geophys. Res."},{"key":"ref_18","first-page":"1892","article-title":"Aerosol climatology over four AERONET sites: An overview","volume":"8","author":"Kambezidis","year":"2007","journal-title":"Atmos. Environ."},{"key":"ref_19","unstructured":"Shettle, E.P., and Fenn, R.W. (1979). Models of Aerosols of Lower Troposphere and the Effect of Humidity Variations on Their Optical Properties, Air Force Cambridge Research Laboratory. AFCRL Technical Report 790214."},{"key":"ref_20","unstructured":"Keopke, P., Hess, M., Schult, I., and Shettle, E.P. (1997). Global Aerosol Data Set, Max-Planck-Institut f\u00fcr Meteorologie. MPI Meteorologie Hamburg Rep."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1747","DOI":"10.5194\/amt-6-1747-2013","article-title":"MODIS 3 km aerosol product: Applications over land in an urban\/suburban region","volume":"6","author":"Munchak","year":"2013","journal-title":"Atmos. Meas. Tech."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1829","DOI":"10.5194\/amt-6-1829-2013","article-title":"MODIS 3 km aerosol product: Algorithm and global perspective","volume":"6","author":"Remer","year":"2013","journal-title":"Atmos. Meas. Tech."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1435","DOI":"10.1117\/1.JRS.8.083612","article-title":"High temporal resolution aerosol retrieval using Geostationary Ocean Color Imager: Application and initial validation","volume":"8","author":"Zhang","year":"2014","journal-title":"J. Appl. Remote Sens."},{"key":"ref_24","first-page":"173","article-title":"High-resolution aerosol remote sensing retrieval over urban areas by synergetic use of HJ-1 CCD and MODIS data","volume":"46","author":"Li","year":"2012","journal-title":"Atmos. Environ."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"8760","DOI":"10.3390\/rs6098760","article-title":"Inversion of Aerosol Optical Depth Based on the CCD and IRS Sensors on the HJ-1 Satellites","volume":"6","author":"Zhang","year":"2014","journal-title":"Remote Sens."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.rse.2016.04.008","article-title":"Preliminary analysis of the performance of the Landsat 8\/OLI land surface reflectance product","volume":"185","author":"Vermote","year":"2016","journal-title":"Remote Sens. Environ."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1016\/j.atmosres.2014.08.012","article-title":"Improved aerosol retrieval algorithm using Landsat images and its application for PM10 monitoring over urban areas","volume":"153","author":"Luo","year":"2015","journal-title":"Atmos. Res."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Sun, L., Wei, J., Bilal, M., Tian, X., Jia, C., and Guo, Y. (2016). Aerosol Optical Depth Retrieval over Bright Areas Using Landsat 8 OLI Images. Remote Sens., 8.","DOI":"10.3390\/rs8010023"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2668","DOI":"10.3390\/rs70302668","article-title":"A Multi-Temporal and Multi-Spectral Method to Estimate Aerosol Optical Thickness over Land, for the Atmospheric Correction of FormoSat-2, LandSat, VEN\u03bcS and Sentinel-2 Images","volume":"7","author":"Hagolle","year":"2015","journal-title":"Remote Sens."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Popp, T., de Leeuw, G., Bingen, C., Bruhl, C., Capelle, V., Chedin, A., Clarisse, L., Dubovik, O., Griesfeller, J., and Heckel, A. (2016). Development, production and evaluation of aerosol climate data records from European satellite observations (Aerosol_cci). Remote Sens., 8.","DOI":"10.3390\/rs8050421"},{"key":"ref_31","first-page":"90","article-title":"Simultaneous retrieval of aerosol and surface properties from a combination of AERONET and satellite data","volume":"107","author":"Sinyuk","year":"2007","journal-title":"Remote Sens."},{"key":"ref_32","first-page":"353","article-title":"Quickly atmospheric correction for GF-1 WFV cameras","volume":"20","author":"Wang","year":"2016","journal-title":"J. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"5544","DOI":"10.1109\/TGRS.2016.2568246","article-title":"High-Spatial-Resolution Aerosol Optical Properties Retrieval Algorithm Using Chinese High-Resolution Earth Observation Satellite I","volume":"54","author":"Bao","year":"2016","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_34","unstructured":"Lawson, C., and Hanson, R. (1974). Solving Least Squares Problems, Prentice-Hall."},{"key":"ref_35","first-page":"775","article-title":"Development of China high-resolution earth observation system","volume":"20","author":"Tong","year":"2016","journal-title":"J. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/S0034-4257(02)00078-0","article-title":"Global land cover mapping from modis: Algorithms and early results","volume":"83","author":"Friedl","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Bassani, C., Manzo, C., Zakey, A., and Cuevas-Agull\u00f3, E. (2016). Effect of the Aerosol Type Selection for the Retrieval of Shortwave Ground Net Radiation: Case Study Using Landsat 8 Data. Atmosphere, 7.","DOI":"10.3390\/atmos7090111"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Holzer-Popp, T., Schroedter, M., and Gesell, G. (2002). Retrieving aerosol optical depth and type in the boundary layer over land and ocean from simultaneous GOME spectrometer and ATSR-2 radiometer measurements, 1, Method description. J. Geophys. Res. Atmos., 107.","DOI":"10.1029\/2001JD002013"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"2411","DOI":"10.5194\/amt-7-2411-2014","article-title":"Retrieval of aerosol optical depth over land surfaces from AVHRR data","volume":"7","author":"Mei","year":"2014","journal-title":"Atmos. Meas. Tech."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Mei, L., Rozanov, V., Vountas, M., Burrows, J.P., Levy, R.C., and Lotz, W. (2016). Retrieval of aerosol optical properties usingMERIS observations: Algorithm and some first results. Remote Sens. Environ.","DOI":"10.1016\/j.rse.2016.11.015"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Levy, R.C., Remer, L.A., and Dubovik, O. (2007). Global aerosol optical properties and application to Moderate Resolution Imaging Spectroradiometer aerosol retrieval over land. J. Geophys. Res. Atmos., 112.","DOI":"10.1029\/2006JD007815"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"5575","DOI":"10.5194\/amt-9-5575-2016","article-title":"Improved MODIS DT aerosol optical depth algorithm over land: Angular effect correction","volume":"9","author":"Wu","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_43","unstructured":"Vermote, E.F., Roger, J.C., and Ray, J.P. MODIS Surface Reflectance User\u2019s Guide, Collection 6, 2015. Available online: http:\/\/modis-sr.ltdri.org\/guide\/MOD09_UserGuide_v1.4.pdf."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Zhang, Q., Xin, J., Yan, Y., Wang, L.L., and Wang, Y. (2016). The Variations and Trends of MODIS C5 & C6 Products\u2019 Errors in the Recent Decade over the Background and Urban Areas of North China. Remote Sens., 8.","DOI":"10.3390\/rs8090754"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0034-4257(98)00031-5","article-title":"AERONET \u2013 A federated instrument network and data archive for aerosol characterization","volume":"66","author":"Holben","year":"1998","journal-title":"Remote Sens. Environ."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1109\/36.581987","article-title":"Second Simulation of the Satellite Signal in the Solar Spectrum, 6S: An overview","volume":"35","author":"Vermote","year":"1997","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.atmosres.2004.07.004","article-title":"A parameterization of the diffuse transmittance and reflectance for aerosol remote sensing problems","volume":"73","author":"Kokhanovsky","year":"2005","journal-title":"Atmos. Res."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1773","DOI":"10.1364\/AO.19.001773","article-title":"New determination of Rayleigh scattering in the terrestrial atmosphere","volume":"19","author":"Shaw","year":"1980","journal-title":"Appl. Opt."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"20791","DOI":"10.1029\/93JD02072","article-title":"Coupled surface-atmosphere reflectance (CSAR) model: 2. Semiempirical surface model usable with NOAA advanced very high resolution radiometer data","volume":"98","author":"Rahman","year":"1993","journal-title":"Geophys. Res. Atmos."},{"key":"ref_50","first-page":"16","article-title":"Image Radiometric and Geometric Accuracy Evaluation of GF-4 Satellite","volume":"4","author":"Xu","year":"2016","journal-title":"Spacecr. Recovery Remote Sens."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"7619","DOI":"10.5194\/acp-15-7619-2015","article-title":"Ground-based aerosol climatology of China: Aerosol optical depths from the China Aerosol Remote Sensing Network (CARSNET) 2002\u20132013","volume":"15","author":"Che","year":"2015","journal-title":"Atmos. Chem. Phys."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"1708","DOI":"10.1007\/s11434-007-0222-0","article-title":"Validation of MODIS aerosol products by CSHNET over China","volume":"52","author":"Wang","year":"2007","journal-title":"Chin. Sci. Bull."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1129","DOI":"10.5194\/amt-3-1129-2010","article-title":"Fast and simple model for atmospheric radiative transfer","volume":"3","author":"Seidel","year":"2010","journal-title":"Atmos. Meas. Tech."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"151","DOI":"10.5194\/amt-4-151-2011","article-title":"Retrieval of spectral aerosol optical thickness over land using ocean color sensors MERIS and SeaWiFS","volume":"4","author":"Yoon","year":"2011","journal-title":"Atmos. Meas. Tech."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Mei, L., Rozanov, V., Vountas, M., Burrows, J.P., and Richter, A. (2017). XBAER derived aerosol optical thickness from OLCI\/Sentinel-3 observation. Atmos. Chem. Phys., (submitted).","DOI":"10.5194\/acp-2017-223"},{"key":"ref_56","first-page":"D23206","article-title":"Three-dimensional variational assimilation of MODIS aerosol optical depth: Implementation and application to a dust storm over East Asia","volume":"116","author":"Liu","year":"2011","journal-title":"J. Geophys. Res."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"4043","DOI":"10.1002\/2013JD020937","article-title":"Assimilating aerosol observations with a \u201chybrid\u201d variational-ensemble data assimilation system","volume":"119","author":"Schwartz","year":"2014","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"20455","DOI":"10.1029\/92JD01411","article-title":"A bidirectional reflectance model of the Earth\u2019s surface for the correction of remote sensing data","volume":"97","author":"Roujean","year":"1992","journal-title":"J. Geophys. Res."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/S0034-4257(02)00091-3","article-title":"First operational BRDF, albedo nadir reflectance products from MODIS","volume":"83","author":"Schaaf","year":"2003","journal-title":"Remote Sens. Environ."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/3\/253\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:30:06Z","timestamp":1760207406000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/3\/253"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,3,9]]},"references-count":59,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2017,3]]}},"alternative-id":["rs9030253"],"URL":"https:\/\/doi.org\/10.3390\/rs9030253","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,3,9]]}}}