Nwamekwe, C. O., C. C. Okpala, and E. C. Nwabunwanne. “Design Principles and Challenges in Achieving Zero-Energy Manufacturing Facilities”. Journal of Engineering Research and Applied Science, Vol. 14, no. 1, June 2025, pp. 1-21, http://www.journaleras.com/index.php/jeras/article/view/373.