Gerhard Kuntschik and Pablo Elizalde. Wolff: Value of privateers will rise. autosport.com (Haymarket Publications). 2009-11-20 [2013-09-01]. (原始内容存档于2017-06-30) (英语).
Gerhard Kuntschik and Pablo Elizalde. Wolff: Value of privateers will rise. autosport.com (Haymarket Publications). 2009-11-20 [2013-09-01]. (原始内容存档于2017-06-30) (英语).