The electronic properties of the organic superconductor (BEDO-TTF)(2)R
eO4(H2O) were investigated by temperature dependent resistivity, FT -
IR reflectivity and magnetoresistance measurements. Shubnikov-de Haas
(SdH) oscillations were observed in magnetic fields up to 24T in the t
emperature range from 0.5K to 4.2K. The two observed SdH(.) frequencie
s of 76 and 37 Tesla correspond very well to two cross-sectional areas
of the Fermi surface obtained from a tight binding calculation for a
hole and an electron pocket.