Merkel B. Groundwater geochemistry / B. Merkel, B. Planer-Friedrich, 2005 r=on-line. - Текст : электронный.
Merkel B. Groundwater geochemistry : a practical guide to modeling of natural and contaminated aquatic systems / B. Merkel, D. Nordstrom, B. Planer-Friedrich, 2008 r=on-line. - Текст : электронный.