Waterman classes and piecewise monotone approximations / A. N. Bakhvalov. // Vestnik Moskovskogo Universiteta. Seriya 1. Matematika. Mekhanika. 2009. ? 6. P. 46-48 [Moscow Univ. Math. Bulletin. Vol. 64, N 6, 2009. P. 259-261].

A neсessary and sufficient condition for a class of functions with a given estimate on piecewise monotone approximations to be embedded into the Waterman class (of functions of bounded \Lambda-variation) is obtained.

Key words: piecewise monotone approximation, genezalized variation.