The Minneola tangelo (sometimes misspelled "Mineola") is a cross between a Duncan grapefruit and a Dancy tangerine, and was released in 1931 by the USDA Horticultural Research Station in Orlando. The skin is usually thin on the Minneola and should peel fairly easily. Most Minneolas have a stub protruding neck stem which gives them a bell shape.
http://en.wikipedia.org/wiki/Tangelo
References
http://viverojugoza.com/index.php?option=com_content&view=article&id=53&Itemid=25?