- Hatata (First Inquiry)
- By: Zera Jacobs (Originally Published in 1667)
- Inquiry Into Reason (Second Inquiry)
- By: Walda Heywat
- Zara Yacob: Rationality of the Human Heart
- By: Kiros, Teodros. The Red Sea Press, Inc. (July 1, 2005)
- Ethiopian Philosophy, vol. II: The Treatise of Zera Yaecobs and Walda Hewat: Text and Authorship, Commercial Press, (1976)
- By: Sumner, Claude