On one-relator quotients of the modular group [chapter]

Marston Conder, George Havas, M. F. Newman, C. M. Campbell, M. R. Quick, E. F. Robertson, C. M. Roney-Dougal, G. C. Smith, G. Traustason
Groups St Andrews 2009 in Bath  
doi:10.1017/cbo9780511842467.011 fatcat:xn3uh7dfbzbgjhfytlkqh56y74