Many thanks to Ernst van Loon: "Just a correction: this is a JA-37. The number 39 is used for its successor, the 'Gripen'.
http://www.pbase.com/ernst/profile
Trivia: The Viggen was the inspiration for Burt Rutan to build the Vari-Viggen in 1970. His conclusion: Using wood, aluminum, and fiberglas was too complicated. It took four years for Burt to build the Vari-Viggen. He decided to design a new homebuilt that would be very easy to build and called it the Varieze. His first wife said, "Either that plane goes or I go." Burt's comment, "I did not realize it would such a vari-eze decision to make." And the Varieze revolutionized homebuilding aircraft. It took Burt six months to build the Vari-Eze.