1.  Sunghoon Park and Dewey D.Y.Ryu, 1989
"Effect of operating parameters on TrpA productivity and performance of a recombinant fermentation process in a two-stage continuous fermentation"
Biotechnol. Bioeng. Vol.35, P.287-295

2. Sun Bok Lee, Dewey D.J. Ryu, Roert Siegel and Sunghoon Park, 1988
"Performance of recombinant fermentation and evaluation of gene expression efficiency for gene product in a two-stage continuous culture system"
Biotechnol. Bioeng. Vol.31, P.805-820

3. Dewey D.Y.Ryu and Sunghoon Park, 1987
"Genetically structured kinetic model for gene product and application of gene switching system to fermentation process control"
Annals of the New York Academy of Science, Vol.506,P.396-405