https://dongten.net/category/tri-thuc/than/
https://xuanbichvietnam.wordpress.com/tag/th%e1%ba%a7n-h%e1%bb%8dc/
http://www.simonhoadalat.com/Submenu/Sub_doc/Sub_menu3_doc4.html
Đa Minh
http://daminhvn.net/than-hoc.html
https://catechesis.net/category/than-hoc/
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http://www.betrenthuongcap.net/tai-lieu.html
http://giaophanthanhhoa.net/than-hoc.html
12-8-2020
Tôma Sơn.