Steps:
1-go to https://es.wikipedia.org/w/index.php?title=Especial:Traducci%C3%B3n_de_contenidos&campaign=contributionsmenu&to=es&page=Input-to-state+stability&from=en&targettitle=Input-to-state+stability
2-start a translation
3-translate the selected math formula
Possible issues:
- the warning "template unavailable" shows but the template exists in the target language https://es.wikipedia.org/wiki/Plantilla:NumBlk
- the "add new template" button in the warning doesn't do anything