We consider the hierarchy flats, a combinatorial generalization of flat virtual links proposed by Louis Kauffman. An approach to constructing invariants for hierarchy flats is presented; several examples are given.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-fm188-0-7, author = {Vassily O. Manturov}, title = {Flat hierarchy}, journal = {Fundamenta Mathematicae}, volume = {185}, year = {2005}, pages = {147-154}, zbl = {1088.57009}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-fm188-0-7} }
Vassily O. Manturov. Flat hierarchy. Fundamenta Mathematicae, Tome 185 (2005) pp. 147-154. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-fm188-0-7/