Ekders.com

Study Group Stirling Engines
Project target is to develop an engine with significant output power. Includes historical and scientific background, news, project information and pictures. [English, German]
members.aol.com/

HowStuffWorks - How Stirling Engines Work
Describes the thermodynamic cycle. Includes several animated diagrams.
www.howstuffworks.com/

Compact Radial Engines
Manufactures and distributes radial, boxer and inline aircraft engines for experimental, PPG and ultralight aircraft.
www.compactradialengines.com/

Bill and Nancy DeWire's Hit-and-Miss Gas Engines
Bill and Nancy DeWire have been collecting and restoring hit-and-miss gas engines for 40+ years in Hughesville, Pennsylvania. Also have antique cars, tractors and other farm machinery.
www.dewireengines.741.com/

Leo Engines Industry
Manufacturer of model engines for air craft, helicopter, boat, car accessories, agricultural and accessories.
www.leoengines.com/

Mathe Engines
Large-displacement gas engines for boat, airplane and cars.
matheengines.com/

O.S. Engines
Line includes airplane, car and buggy, helicopter and boat engines.
www.osengines.com/

RCV Engines
Develop and design engines for aircraft models, motorcycles and small airplane. UK.
www.rcvengines.com/

Chuck's Hit n Miss Gasolene Engines
Helpful hints and parts for the care of antique engines.
www.angelfire.com/

Zanzottera Engines
Manufacturer of engines designed for ultralight and unmanned aircraft.
www.zanzotteraengines.com/