New Constructions of the Lattice-Based Visual Secret Sharing Scheme Using Mixture of Colors. - Takeru Ishihara; Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2002)

A Visual Secret Sharing Scheme for Color Images Based on Meanvalue-Color Mixing. - Takeru Ishihara; Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2003)

Construction of Threshold (Hybrid) Encryption in the Random Oracle Model: How to Construct Secure Threshold Tag-KEM from Weakly Secure Threshold KEM. - Takeru Ishihara; Hiroshi Aono; Sadayuki Hongo; Junji Shikata (ACISP, 2007)

A general method for construction of (t, n)-threshold visual secret sharing schemes for color images. - Hiroki Koga; Takeru Ishihara (Des. Codes Cryptogr., 2011)