Bektenov Nesiphan Abzhaparovich, Murzakassymova Nazgul Sattarkulovna, Gavrilenko Mikhail Alekseevich, и Nurlybayeva Аisha Nurlybayevna. «PRODUCTION OF SULFOCATIONITE BY MODIFICATION OF NATURAL COAL WITH CONCENTRATED SULFURIC ACID». Известия НАН РК. Серия химии и технологии, вып. 3, июнь 2020 г., сс. 104-9, http://89.250.84.46/chemistry-technology/article/view/982.