1. N. Bourbaki, General Topology: Chapters 5–10, Springer-Verlag, Berlin, 1998.
2. M. Frank and D. R. Larson, “A module frame concept for Hilbert $$C^\ast$$-modules”, Contemp. Math., vol. 247 Amer. Math. Soc., Providence, RI, 1999, 207–233,.
3. M. Frank and D. R. Larson, “Frames in Hilbert $$C^\ast$$-modules and $$C^\ast$$-algebras”, J. Operator Theory, 48:2 (2002), 273–314.
4. G. G. Kasparov, “Hilbert C*-modules: Theorems of Stinespring and Voiculescu”, J. Opererator Theory, 4 (1980), 133–150.
5. D. J. Kečkić and Z. Lazović, “Compact and “compact” operators on standard Hilbert modules over $$W^*$$-algebras”, Ann. Funct. Anal., 9:2 (2018), 258–270; arXiv: 1610.06956.