Deduction form of Theorem 19.21 of [Margaris] p. 90, see 19.21 and 19.21h. (Contributed by NM, 10-Feb-1997.) (Proof shortened by Andrew Salmon, 13-May-2011.)
Deduction form of Theorem 19.21 of [Margaris] p. 90, see 19.21 and 19.21h. (Contributed by NM, 10-Feb-1997.) (Proof shortened by Andrew Salmon, 13-May-2011.)