H. Mahmoodnia, A. Salehi, V. R. Mastelaro, “GaAs semiconductor passivated by (NH$_4$)$_2$S$_x$ : analysis of different passivation methods using electrical characteristics and XPS measurements”, Fizika i Tekhnika Poluprovodnikov, 54:7 (2020), 691; Semiconductors, 54:7 (2020), 817–826
