The influence of the partial Ca substitution on the microstructure of YBCO tapesTerzieva, Stanimira; Stoyanova-Ivanova, Angelina; Mikli, Valdek; Zahariev, A.; Angelov, Christo; Dimitriev, Yanko; Kovachev, V.Journal of optoelectronics and advanced materials2007 / 2, p. 453-455 https://www.researchgate.net/publication/286222792_The_influence_of_the_partial_Ca_substitution_on_the_microstructure_of_YBCO_tapes