They don't tell us who their author is. Notice, they're not pseudonymous.

他们没有说作者是何许人，而且，他们也没有使用笔名。

耶鲁公开课 - 新约课程节选

Pseudonymous means it's published with a false name, a false author attributed.

笔名的意思是用一个假名发表，以一个假作者的名义。

耶鲁公开课 - 新约课程节选