1. Journal of Mathematics and Physics;Heins;The coupling of two acoustical ducts,1947
2. Journal of Sound and Vibration;Lansing;Effects of wall admittance changes on duct transmission and radiation of sound,1973
3. NASA TR R-419;Zorumski;Acoustic theory of axisymmetric multisectioned ducts,1974
4. 89th Meeting of the Acoustical Society of America, Paper H1;Beckemeyer,1975
5. AIAA 2nd Aero-Acoustics Specialist Conference, AIAA Paper 75-518;Baumeister,1975