113

T. W. Palmer, C. Hornung, M. A. Gruber, J. Scheffer, Cooper D. Schmitt, J. C. Nagle, Chas. C. Cross, J. O. Mahoney
1899 The American mathematical monthly  
doi:10.2307/2971417 fatcat:vv3kvjnz55fpvjja5rxpyitrnm