[1] A. Dvurečenskij, S. Pulmannová: 
New trends in Quantum Structures Theory. Kluwer Academic Publications, Dordrecht / Ister Science, Bratislava 2000. 
MR 1861369 
[3] G. Jenča, Z. Riečanová: On sharp elements in lattice ordered effect algebras. BUSEFAL 80 (1999), 24-29.
[5] V. Olejček: 
An atomic MV-effect algebra with non-atomic center. Kybernetika 43 (2007), 3, 343-346. 
MR 2362723 | 
Zbl 1149.06006 
[6] V. Olejček: 
Uniformly Archimedean MV-effect algebra is sharply dominating. Kybernetika 46 (2010), 6, 948-952. 
MR 2797419 
[7] Z. Riečanová: 
Modular atomic effect algebras and the existence of subadditive states. Kybernetika 40 (2004), 4, 459-468. 
MR 2102364 
[8] Z. Riečanová, I. Marinová, M. Zajac: Some aspects of generalized prelattice effect algebras. In: Lecture Notes in Artificial Intelligence (LNAI) 4342 ``Theory and Application of Relational Structures as Knowledge Instruments II"(H. de Swart et all, eds.), Springer 2006, pp. 290-317.