1 2 3 Marcin Peczarski, New results in minimum-comparison sorting, Algorithmica 40 (2), 133–145, 2004. ↑ Marcin Peczarski, Computer assisted research of posets, PhD thesis, University of Warsaw, 2006. ↑ Peczarski, Marcin (2007). "The Ford-Johnson algorithm is still unbeaten for less than 47 elements". Inf.