{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T18:24:09Z","timestamp":1775845449792,"version":"3.50.1"},"reference-count":21,"publisher":"Canadian Mathematical Society","issue":"5","license":[{"start":{"date-parts":[[2018,11,20]],"date-time":"2018-11-20T00:00:00Z","timestamp":1542672000000},"content-version":"unspecified","delay-in-days":2972,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can. j. math."],"published-print":{"date-parts":[[2010,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>We address the problem of computing the fundamental group of a symplectic<jats:italic>S<\/jats:italic><jats:sup>1<\/jats:sup>-manifold for non-Hamiltonian actions on compact manifolds, and for Hamiltonian actions on non-compact manifolds with a proper moment map. We generalize known results for compact manifolds equipped with a Hamiltonian<jats:italic>S<\/jats:italic><jats:sup>1<\/jats:sup>-action. Several examples are presented to illustrate our main results.<\/jats:p>","DOI":"10.4153\/cjm-2010-053-3","type":"journal-article","created":{"date-parts":[[2010,7,6]],"date-time":"2010-07-06T20:17:16Z","timestamp":1278447436000},"page":"1082-1098","source":"Crossref","is-referenced-by-count":2,"title":["The Fundamental Group of<i>S<\/i><sup>1<\/sup>-manifolds"],"prefix":"10.4153","volume":"62","author":[{"given":"Leonor","family":"Godinho","sequence":"first","affiliation":[]},{"given":"M. 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