1.
MRUCZEK-NASIENIEWSKA, Krystyna. Externally compatible Abelian groups of the type (2,1,0). Logic and Logical Philosophy. Online. 15 March 2007. Vol. 15, no. 3, pp. 239-250. [Accessed 25 July 2024]. DOI 10.12775/LLP.2006.014.