[1]

T.A. Loring. Almost multiplicative maps between C*-algebras. In Operator algebras and quantum field theory (Rome, 1996), pages 111-122. Internat. Press, Cambridge, MA, 199?

[2]

G. K. Pedersen. Extensions of C*-algebras. In Operator algebras and quantum field theory (Rome, 1996), pages 1-35. Internat. Press, Cambridge, MA, 199?

[3]

Gert K. Pedersen. Pullback and pushout constructions in C*-algebra theory. J. Funct. Anal., 167(2):243-344, 1999.