Full paper in PDF:
$%A. Shima, An unknotting theorem for tori in S4, Rev. Mat. Complut. 11 (1998), no. 2,
299–309.%$
Let be a torus in and a projection of . If the singular set consists of one disjoint simple closed curve, then can be moved to the standard position by an ambient isotopy of .
1991 Mathematics Subject Classification: Primary: 57Q45; secondary: 57Q35.