DOBROTVORSKAYA М.В., OBOLENSKU М.А., POLTORATSK1I Ю.Б. and SOBOLEV В.Л. 1990. X-ray photoelectron spectra of La₂CuO₄ doped with strontium and scandium. FIZYKA NYZKYKH TEMPERATUR. 16, 11 (Nov. 1990), 1387–1395.