1. E. Berlekamp, On a problem of Persi Diaconis, an unpublished manuscript
2. Universal cycles for combinatorial structures;Chung;Discrete Math.,1992
3. G. Hurlbert, Universal cycles: On beyond De Bruijn, Ph.D. thesis, Rutgers University, 1990
4. On universal cycles for k-subsets of an n-set;Hurlbert;SIAM J. Discrete Math.,1994
5. G. Hurlbert, T. Johnson, J. Zahl, On universal cycles for multisets (submitted for publication). arXiv:math/0701488v2