When did they stop making the Buffalo Nickels?

I know it is a oxen on the nickel. The lady in the cafeteria gave me one today not knowing what it was. The date is un-readable from age. I need to know when they stoped making it so i can assume it was the latest date. I would like you to include a link. Also one to a good coin site.

Indian Head 5 cents a.k.a. Buffalo Nickel :

The animal depicted
=> American Bison

Minted from
=> 1913 to 1938

Minted at
=> Philadelphia, Denver and San Francisco

Metal composition:
=> 75% copper, 25% nickel

Varieties
=> Type 1:Bison on mount http://www.buffalonickel.com/images/260_BN1913_T1_1r.jpg
=> Type 2:Bison on plain http://en.wikipedia.org/wiki/Image:1935_Indian_Head_Buffalo_Nickel.jpg

Value
=> Dateless "Buffalo nickels" are about 5 to 10 cents the most.

Website links & Articles
=> http://www.buffalonickel.com/
=> http://www.scvhistory.com/scvhistory/signal/coins/sg091705-coins.htm
=> http://www.collectorusa.com/articles/buffalo5c.php