@article{Savage1997, 
     author = "Savage, Carla", 
     doi = "10.1137/S0036144595295272", 
     issn = "0036-1445", 
     journal = "SIAM Review", 
     keyword = "acyclic orientations,binary strings,boolean lattice,catalan families,cayley graphs,combinations,compositions,de bruijn sequences,gray codes,hamilton cycles,integer parti-,linear extensions,necklaces,permutations,restricted growth functions,set partitions,tions,vertex-", 
     link = "http://epubs.siam.org/doi/abs/10.1137/S0036144595295272", 
     month = "jan", 
     number = "4", 
     pages = "605--629", 
     title = "A Survey of Combinatorial Gray Codes", 
     uri = "http://epubs.siam.org/doi/abs/10.1137/S0036144595295272", 
     volume = "39", 
     year = "1997", 
}

Problems: 329