1. The Modification of the Kjeldahl Method for the Quantitative Determination of Nitrogen;Hepburn;J. Franklin Inst,1908
2. Kjeldahl and The Determination of Nitrogen;Oesper;J. Chem. Educ,1934
3. The Kjeldahl Determination of Organic Nitrogen;Bradstreet;Chem. Rev,1940
4. The Kjeldahl Method in the Past and Present;Frankignoulle;Z. ges. Brauw,1942
5. Sarudi's Rapid Method for Kjeldahl Nitrogen Determination;Smith;Tidsskr. Norske Landbruk,1942