German standard methods for examination of water, waste water and sludge - Cations (group E) - Part 8: Determination of zinc - Method by atomic absorption spectrometry (AAS) using an air-ethine flame (E 8)— 20 стр.
Methods of soil investigations for agricultural engineering - Chemical laboratory tests - Part 10: Testing and evaluation of water for irrigation— 11 стр.
German standard methods for examination of water, waste water and sludge - Cations (group E) - Part 8: Determination of zinc - Method by atomic absorption spectrometry (AAS) using an air-ethine flame (E 8)— 20 стр.