https://blog.gongquiz.com/2022/05/02/crm%ec%9d%98-%eb%aa%a9%ec%a0%81%ec%9d%80-%ea%b3%a0%ea%b0%9d%ec%9d%98-%ec%9d%b4%ec%9d%b5-%ea%b7%b9%eb%8c%80%ed%99%94%ec%99%80-%ec%9d%b4%eb%a5%bc-%ed%86%b5%ed%95%b4-%ea%b8%b0%ec%97%85%ec%9d%98-%ec%88%98/