%0 Journal Article %A N.S. Mendelsohn %A D.M. Johnson %T Extended Triple Systems. %J Aequationes mathematicae %D 1972 %P 291-298 %V 8 %I mathdoc %U http://geodesic.mathdoc.fr/item/AM2_1972__8_136304/ %F AM2_1972__8_136304