Provably secure block ciphers
Construction of provably-secure block ciphers are considered in the following papers:


Pseudo-Random Permutation Generators and Cryptographic Composition by Luby &amp; Rackoff. Full version of this paper can be found in How to Construct Pseudorandom Permutations from Pseudorandom Functions.
On the Construction of Pseudo-Random Permutations: Luby-Rackoff Revisited by Naor &amp; Reingold. This is in fact a revised version of the above ideas by Luby &amp; Rackoff. Full version can be found in here.


The construct by Pat Morin and many others are reviewed in Building Secure Block Ciphers on Generic Attacks Assumptions.