HPOCA CHAPTERS
The Hart-Parr Oliver Collectors Assn. http://www.hartparroliver.org/index.html
The Badgerland Oliver Collectors Assn. http://www.badgerlandolivercollectors.com
The Iowa Corn Belt Oliver Colectors http://cornbeltolivercollectors.org/
The Oliver Gang http://olivergang.org/og/
The Central States Hart - Parr Oliver Collectors Assn. http://www.centralstatesoliver.com/
The Tri-State Hart - Parr Oliver Collectors http://www.tri-stateoliverclub.com/
The California Oliver Cletrac Collectors http://www.calolivercletrac.org/
Great Northern Oliver (Southern MN, Northern Iowa) http://www.GreatNorthernOliver.com