Yavidov, B., G. Saburova, K. Nurimbetov, and M. Ollomberganova. 2020. “BEYKER-KEMPBEL-XAUZDORF FORMULASIGA OID BIR MASALANING YECHILISH METODIKALARI”. ILIM Hám JÁMIYET, no. 3-2 (September): 107-9. https://journal.ndpi.uz/ss/article/view/2020-3-2-045.