# Whole number rule

> Physical law for the masses of isotopes

**Wikidata**: [Q2920462](https://www.wikidata.org/wiki/Q2920462)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Whole_number_rule)  
**Source**: https://4ort.xyz/entity/whole-number-rule


## References

1. Freebase Data Dumps. 2013