For those interested in how and when his contribution was discovered, 
I would like to mention my own paper: 
 
Yukihiro Ikeda, 
Hermann Heinrich Gossen: a Wirkungsgeschichte of an Ignored Mathematical 
Economist, Journal of Economic Studies, vol. 27, No.4/5, 2000. 
 
Good luck! 
 
Yukihiro Ikeda 
Keio University