:: deftheorem Def21 defines non-Dmulti GLIB_000:def 21 :
for G being _Graph holds
( G is non-Dmulti iff for e1, e2, v1, v2 being object st e1 DJoins v1,v2,G & e2 DJoins v1,v2,G holds
e1 = e2 );