Nuclear Matrix Elements of 0νββ-Decay: Possible Test of the Calculations

A possible model independent test of the theoretically calculated nuclear matrix elements of $0\nu\beta\beta$-decay is proposed. The test can be accomplished if $0\nu\beta\beta$-decay of three (or more) nuclei is observed. The selection of the nuclei for the next generation of $0\nu\beta\beta$-decay experiments should be done taking into account {\it also} considerations regarding the possibility to test the nuclear matrix element calculations.