Unknotting virtual knots with Gauss diagram forbidden moves
arXiv:math/0007015
Abstract
The forbidden moves can be combined with Gauss diagram Reidemeister moves to obtain move sequences with which we may change any Gauss diagram (and hence any virtual knot) into any other, including in particular the unknotted diagram
5 pages; see http://www.math.lsu.edu/~nelson for a higher resolution version and more about virtual knots