00441naa#a2200157#i#450# EN\\bibl\23317 20240419201557.5 2542-1840 20180525b2018####ek#y0engy0150####ca RU SERVICES AGREEMENT: CONCLUSION AND EXECUTION Journal article Kemerovo Kemerovo State University 2018 5 с. Journal article local Badziak N. E. jcenter.kemsu.ru