Def b_exists_unique('a;x.p(x))
Def == (x:'a. p(x))(x,y:'a.  (p(x)p(y))(x = y))

is mentioned by

Thm* p:('a).  Thm* b_exists_unique('a;x.p(x)) Thm*  Thm* (x:'a. p(x)) & (x,y:'a. p(x) & p(y)  x = y)	[assert_of_b_exists_unique]
Def exists_unique == p:'a. b_exists_unique('a;x.p(x))	[hexists_unique]

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