Chlorofluorocarbons (CFCs) are the only major contributor to the greenhouse effect that does not occur naturally, coming from such sources as refrigeration, plastics and manufacture.
Англо-русский строительный словарь. — М.: Русский Язык.С.Н.Корчемкина, С.К.Кашкина, С.В.Курбатова.1995.