BOCA, Florin. Completely positive maps on amalgamated product $C^*$-algebras. Mathematica Scandinavica, Berkeley, CA, United States, v. 72, p. 212–222, 1993. DOI: 10.7146/math.scand.a-12445. Disponível em: https://journals.msp.org/mscand/article/view/1182. Acesso em: 24 jul. 2026.