[IEEE 2017 2nd International conferences on Information Technology, Information Systems and Electrical Engineering (ICITISEE) - Yogyakarta, Indonesia (2017.11.1-2017.11.2)] 2017 2nd International conferences on Information Technology, Information Systems and Electrical Engineering (ICITISEE) - Implementation of data mining technique for customer relationship management (CRM) on online shop tokodiapers.com with fuzzy c-means clustering