束について
http://en.wikipedia.org/wiki/Lattice_%28order%29
http://en.wikipedia.org/wiki/Semilattice
http://en.wikipedia.org/wiki/Distributive_lattice
http://en.wikipedia.org/wiki/Distributivity_%28order_theory%29
http://en.wikipedia.org/wiki/Completeness_%28order_theory%29
http://en.wikipedia.org/wiki/Ideal_%28order_theory%29
http://en.wikipedia.org/wiki/Boolean_prime_ideal_theorem
http://en.wikipedia.org/wiki/Galois_connection
ついでにこの際、あまり分かってないことをリストアップ。
http://en.wikipedia.org/wiki/Free_group
http://en.wikipedia.org/wiki/Free_object
http://en.wikipedia.org/wiki/Module_%28mathematics%29
http://en.wikipedia.org/wiki/Universal_algebra