1. Jordbundsbedømmelse ved brug af hydrometer (Soil determination by means of a hydrometer);Aslyng;Hedeselskabets Funktionaerblad,1953
2. Bepaling van het kleigehalte in grond met behulp van een hydrometer. (Determination of the colloidal content of soils with the aid of a hydrometer.);Beverwijk;Intern. Rept. Rijksdienst IJsselmeerpolders,1967
3. The hydrometer as a new rapid method for determining the colloidal content of soils;Bouyoucos;Soil Sci.,1927
4. The hydrometer as a new method for the mechanical analysis of soils;Bouyoucos;Soil Sci.,1927
5. The hydrometer method for making a very detailed mechanical analysis of soils;Bouyoucos;Soil Sci.,1928