🌐EnglishEnglishEspañolPolskiРусский中文日本語EntityQ6415019· pop 5· linked from 5 articlesKirchhoff integral theoremMethod to solve scalar wave equationAvailable in 5 languagesEspañol中文РусскийPolskivia Wikidata sitelinks · CC0ConnectionsHuygens–Fresnel principleEntityGreen's identitiesEntityCategoriesDiffractionGustav KirchhoffPhysical optics