Supercluster what is order of index.getClusters

This is the plugin:

The documentation says that index.getClusters should have this parameters [westLng, southLat, eastLng, northLat]

But google get bounds function returns SW and NE.

My question is: is okay the order [westLng, southLat, eastLng, northLat] = [req.body.SWLng, req.body.SWLat, req.body.NELng, req.body.NELat] ?

My doubt is about westLng and eastLng it doesnt say if there is north or south.

var result = index.getClusters([req.body.SWLng, req.body.SWLat, req.body.NELng, req.body.NELat], req.body.zoom)