Kjellman, W. <br/><br/>
Soil sampler with metal foils device for taking undisturbed- samples of very great length / by W. Kjellman, T. Kallsten-ius, and O. Wager. 

 - [Estocolmo, Suecia] : Royal Swedish Geotechnical Institute 
 - 75 p. 
 - Proceedings; No. 1 .