1. Cenerini R. (1962) Part II of this article series. This issue, p. 29.
2. Kersten J. A. H. (1962) Part I of this article series. This issue, p. 15.
3. Markestein T. and van der Plas (1962) Part III of this article series. This issue, p. 33.
4. Fine Particle Measurement;Orr,1959