Linked from
The 12 pages that link to Yttrium, each with the reason it gives.
ErbiumRelated: Yttrium-bearing minerals can also contain erbium and other lanthanides.
YtterbyBroader topic: It was the first element named for the village.
HolmiumRelated: Yttrium is a common host element in crystals activated by holmium ions.
Group 3 elementBroader topic: It is the other undisputed conventional member of Group 3.