1. Annoyance due to railway noise in residential areas;Walters,1969
2. Noise in the vicinity of railway lines;Rapin;Centre Scientifique et Technique du Batiment, Cahier 1130,1972
3. Noise generated by subways above ground and in stations;Bender;Bolt Beranek and Newman Inc. Technical Report, Contract No. DOT-OS-A9-040,1970