1. Berggren, R.: 1968,Tellus 20, 88.
2. Bischof, W.: 1970,Tellus 22, 545.
3. Borden, T. R.: 1970, ?Extreme Values of Ozone Observed in the AFCRL Ozonesonde Network?, Office of Aerospace Research, USAF.
4. Brabets, R. I.: 1963, ?Ozone Measurements Survey in Commercial Jet Aircraft?, FAA Technical Report ADS-5.
5. Fabian, P. and Pruchnievicz, P. G.: 1970, ?Ozone Measurements Made Aboard a Commercial Airliner?, not published.