[P1] U. Pinkall, Tight surfaces and regular homotopy,
Topology 25 (1986) 475-481.
The author finds tight immersions of all but finitely many of the
classes of immersed surfaces under regular homotopy (but his example
of T#S#S#S is in error, it is actually K_o#T#S#S). He
also shows that there is no tight immersion of the twisted torus,
T, or of K+#B.
10/12/94 dpvc@geom.umn.edu --
The Geometry Center