This page contains references to additional information about certain topics in case you are interested in learning more. None of these are required. Required readings are here.
Peterson, R.G. 1977. Use and misuse of multiple comparison
procedures. Agronomy Journal 69:205-208.
Recommends m.c.p. when 'data snooping', i.e. when looking for
interesting patterns. m.c.p. are 'almost never appropriate' for
quantitative treatments, factorial treatment structures, and
answering specific questions.