@techreport{ChvatalKlarnerKnuth1972,
  author    = {{Vasik Chvatal, David A. Klarner and Donald E. Knuth}},
  title     = {{Selected combinatorial research problems}},
  year      = {{1972}},
  number    = {{STAN-CS-72-292}},
  institution= {{Stanford Computer Science Dept.}},
}