# Grothendieck–Ogg–Shafarevich formula
**Wikidata**: [Q5610735](https://www.wikidata.org/wiki/Q5610735)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Grothendieck–Ogg–Shafarevich_formula)  
**Source**: https://4ort.xyz/entity/grothendieck-ogg-shafarevich-formula