Water quality -- Determination of the growth inhibition effects of waste waters, natural waters and chemicals on the duckweed Spirodela polyrhiza -- Method using a stock culture independent microbiotest— 28 стр.
Magnetic tape sound recording and reproducing systems - Part 4: Mechanical magnetic tape properties (IEC 60094-4:1986 + A1:1994); German version EN 60094-4:1994 + A1:1994— 12 стр.
