<https://social.snu.ac.kr/%ec%a0%95%ec%b9%98%ec%99%b8%ea%b5%90%ed%95%99%eb%b6%80/#breadcrumb>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://social.snu.ac.kr/%EC%A0%95%EC%B9%98%EC%99%B8%EA%B5%90%ED%95%99%EB%B6%80/>