1. Katsura, M. & H. J. Shyr,Decomposition of languages into disjunctive outfix codes, sbmitted for publication.
2. Lyndon, R.C. & M.P. Shützenberger,The equation a
M=b
N
c
P
in a free group, Michigan Math. J. 9 (1962), 289–298.
3. Reis, C.M. & H.J. Shyr,Some properties of dense languages on a free monoid, Inf. and Contr. 37 (1978), 334–344.
4. Shyr, H.J. & G. Thierrin,Locally regular and locally finite languages, Tamkang J. of Math. 10 (1979), 253–262.
5. Lecture Notes;H. J. Shyr,1979