References
- MaceD.J., PennakS., and FinkleM. 1997. Advance Warning Arrow Panel Visibility, NCHRP 5–14 Final Report, FY 93.
- MaceD.J., FinkleM., and GarveyP. 1996. Requirements for Visibility of Symbolic Traffic Signals, FHWA Final Report. DTFH61–92-C-00034.
- PennakS., and FinkleM. (in press). Visibility and Comprehension of Pedestrian Signals, FHWA Final Report. DTFH61–92-C-00034.