O'Loughlin, Eugene (1989) Notes on the distribution of Calliostoma zizyphinum (L.) (Mollusca) on the shores and shallow waters of the Irish coast. Bulletin of the Irish Biogeographical Society , 12. pp. 22-30. ISSN 0032-1185
Sahni, Anu and Grover, P. S. (1989) Computer Techniques to Simulate Surfaces. In: SEARCC 89 : proceedings of the eighth convention of the South East Asia Regional Computer Confederation on information technology into the 21st century, December 5-8 1989. Singapore Computer Society, Singapore, pp. 357-372.