https://www.syu.ac.kr/blog/%ec%97%91%ec%85%80-%ec%b5%9c%ea%b3%a0%ec%9d%98-%ea%b0%95%ec%82%ac-%ec%a0%95%ec%a7%84%ec%9d%bc-%eb%8c%80%ed%91%9c%ea%b0%80-%ec%a7%81%ec%a0%91-%ea%b0%95%ec%9d%98%ed%95%98%eb%8a%94-%ec%97%91%ec%85%80e/%ec%97%91%ec%85%80excel-%eb%8d%b0%ec%9d%b4%ed%84%b0%ea%b4%80%eb%a6%ac_%ea%b0%95%ec%9d%98%ea%b3%84%ed%9a%8d%ec%84%9c/