We present a tameness property of sets definable in o-minimal structures by showing that Morse functions on a definable closed set form a dense and open subset in the space of definable functions endowed with the Whitney topology.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ap89-3-5, author = {Ta L\^e Loi}, title = {Density of Morse functions on sets definable in o-minimal structures}, journal = {Annales Polonici Mathematici}, volume = {89}, year = {2006}, pages = {289-299}, zbl = {1183.14074}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap89-3-5} }
Ta Lê Loi. Density of Morse functions on sets definable in o-minimal structures. Annales Polonici Mathematici, Tome 89 (2006) pp. 289-299. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap89-3-5/