1. Listigovers, N. A.; Allen, C. G.; Martin, T. I.; Hamer, G. K.; Hsiao, C. K.; Baranyi, G.Hydroxygallium Phthalocyanine Pigments with Block Copolymer Binders. U.S. Patent 5,521,043, May 28, 1996.
2. Giambalvo, V. A.; Somerville, N. J.Phthalocyanine Pigment Compositions. U.S. Patent 2,526,345, October 17, 1950.
3. Funatsu, T.; Inuzuka, Y.; Mishina, T.; Kitamura, K.; Chiba, A.Phthalocyanine Pigment Compositions. U.S. Patent 4,221,606, September 9, 1980.
4. Alfred, S.; Summit, N. J.Phthalocyanine Pigments. U.S. Patent 2,861,005, November 18, 1958.
5. Eastes, J. W.; Somerville, N. J.Preparation of Phthalocyanine Pigments. U.S. Patent 2,770,629, November 13, 1956.