Okaya, Y.; K. Vedam; R. Pepinsky. "Non-isomorphism of ferroelectric phases of ammonium sulfate and ammonium fluoberyllate". Acta Crystallographica. 11 (4). 1958: 307. doi:10.1107/s0365110x58000803. ISSN0365-110X.
Okaya, Y.; K. Vedam; R. Pepinsky. "Non-isomorphism of ferroelectric phases of ammonium sulfate and ammonium fluoberyllate". Acta Crystallographica. 11 (4). 1958: 307. doi:10.1107/s0365110x58000803. ISSN0365-110X.