Цахилгаан соронзон харилцан үйлчлэл — Википедиа …
Гадаад холбоос. Electromagnetic Force - from Eric Weisstein's World of Physics; Ties That Bind Atoms Weaker Than Thought - LiveScience; Physics 221B notes – quantization; Physics 221B notes – interaction; Quarked Electromagnetic force - A good introduction for kids