Muhammademinov Alijon Azizjon o‘g‘li, and Saidova Nigora Komiljonovna. 2024. “STEFFENSEN (EYTKEN-STEFFENSEN) USULI”. Ta’lim Innovatsiyasi Va Integratsiyasi 20 (3):97-100. https://web-journal.ru/ilmiy/article/view/4864.