00582naa#a2200181#i#450# EN\\bibl\85966 20241223121003.1 2658-3569 20181225b2018####ek#y0engy0150####ca ENG RU 5 ways preservation and maintenance of the relations with the existing clients by means of CRM systems Journal article Moscow Electronic science 2018 0 с. Journal article local Программные средства. 004.4 ENG Kulikova Maria Mikhailovna qje.su