1. Playing Mastermind With Many Colors
2. On Two Problems in Information Theory;Erdős;Publ. Math. Inst. Hung. Acad. Sci.,1963
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4. Strategies for playing MOO, or “Bulls and Cows”
https://pdfs.semanticscholar.org/d839/f794cccd174790b0cde695d3626f00caf7e1.pdf
5. Mastermind is NP-Complete;Stuckman;INFOCOMP J. Comput. Sci.,2006