기계공학 PDF 2022-1
http://www.dprkmedia.com.00991137000a.erf.sbb.spk-berlin.de/Uploaded/Journal/2106/KPJ_80948.pdf
Mechanical Engineering (dprkmedia) March 12, 2022
http://www.dprkmedia.com.00991137000a.erf.sbb.spk-berlin.de/Uploaded/Journal/2106/KPJ_80948.pdf