Grönefeld 1941 REMONTOIRE- HYPERLINK 1941 Principia-HYPERLINK https://medchem101.online/gronefeld-principia/ The brothers Grönefeld, Bart and Tim, from Oldenzaal in the Netherlands. Two very talented watchmakers from a fine family tradition of watchmaking. Bart and Tim Grönefeld may claim that their grandfather, Johan, began his watchmaking career in the very same location in Oldenzaal…