1. Smith OK, Williams GT (1939) Gas Age 84(3):14–16
2. Anon (1945) American Gas Journal 162(6):47–60
3. White DL, Reichardt FE (1949) Gas 25(6):38–39
4. Austin RR, Percy LE, Escher EE (1950) Gas 26(6):33–36
5. Brychta M, Rudolf J (1956) Paliva 36:307–311