VDI 3793 Blatt 1-1986 Determination of damage to vegetation on natural sites; determination of damage to leafs and/or needles of higher plants by aerial photography with color-infrared film
1990VDI 3793 Blatt 1-1990 On-site determination of vegetational injuries; method of aerial photography with color infrared film
1986VDI 3793 Blatt 1-1986 Determination of damage to vegetation on natural sites; determination of damage to leafs and/or needles of higher plants by aerial photography with color-infrared film