1. Bowman WS, Faye GH, Sutarno R, McKeague JA, Kodama H (1979) Geostandards Newslett 3:109
2. Claisse F, Samson C (1962) Adv X-ray Anal 5:335–354
3. DIN 38414 (1983) Part 7, German Standard Methods
4. Emmermann R, Obi DVC (1971) Fresenius Z Anal Chem 254:1–6
5. Freiburg C, Reichert W, Solomah AG (1985) Multi-element standards from oxide powders for sequential X-ray spectrometers, In: Sansoni (ed) Instrumentelle Multi-Element-Analyse. Verlag Chemie, Weinheim