How to Sort a Collection(API data)?

How to Sort a Collection(API data)?

So, I have something like this:

versionList = Collection();
for each item in searchUrl.getJson("results")
{
year= item.getJson("year");
label= item.getJson("label");
catalog= item.getJson("catalog");
versionList.insert(year + label + catalog);
}

The only way I currently know how to sort this would be versionList.sort(true); One problem is this doesn't seem to sort numbers numerically - it treats 904 as a bigger number than 1004.
I might want to display year first in my data, but sort by catalog.
How might that be done?