Denk, T. & Oh, I.-C. Phylogeny of Schisandraceae based on morphological data: evidence from modern plants and the fossil record. Plant Systematics and Evolution 256: 113-145.
Hong, S. P., Oh, I.-C. and Ronse De Craene, L. P. Pollen morphology of the genera Polygonum s. str. and Polygonella (Polygoneae: Polygonaceae). Plant Systematics and Evolution 254: 13-30.
2003
Oh, I.-C., Denk, T., & Friis, E.-M. Evolution of Illicium (Illiciaceae): Mapping morphological characters on the molecular tree. Plant Systematics and Evolution 240: 175-209.
1999
Oh, I.-C. & Hong, S.-P. A taxonomic study of achene microstructure in the genera PolygonumL. s. str. and Polygonella Michx. (Polygoneae-Polygonaceae). - Korean Journal of Plant Taxonomy 29: 123-134.
Hong, S.-P. & Oh, I.-C. The taxonomic study of leaf epidermal microstructure in the genera Polygonum L. s. str. and Polygonella Michx. (Polygoneae-Polygonaceae). - Korean Journal of Plant Taxonomy 29: 75-90.
1998
Hong, S.-P., Oh, I.-C. & Son, S.-H. Pollen morphology of tribe Pterostegieae Torr. & Gray (Polygonaceae-Eriogonoideae). - Grana 37: 15-21.