Proper noun
Mengel (plural Mengels)
A surname.
At that time, Mengel was traveling between Baltimore and Washington DC to attend anti-war demonstrations. Source: Internet
Fosco and Mengel (2011) And there is the very intriguing paper "The Coevolution of Parochial Altruism and War" by Jung-Kyoo Choi and Samuel Bowles. Source: Internet