Personal guidance system for the visually impaired. - Jack M. Loomis; Reginald G. Golledge; Roberta L. Klatzky; Jon Speigle; Jerome Tietz (ASSETS, 1994)

A Geographical Information System for a GPS Based Personal Guidance System. - Reginald G. Golledge; Roberta L. Klatzky; Jack M. Loomis; Jon Speigle; Jerome Tietz (Int. J. Geogr. Inf. Sci., 1998)