1. 13.060.30 JUS H.Z1. 160 (1987). Testing of industrial waters—Determination of suspended matters—Gravimetric method.
2. APHA AWWA WEF (1992a). 4500-NO $_{3}^{-}$ NITROGEN (NITRATE).
3. APHA AWWA WEF (1992b). 4500-P PHOSPHORUS.
4. APHA AWWA WEF (1992c). Standard methods for the examination of water and wastwater 18th Edition.
5. Avis, C. H., & Weller, P. H. (2000). The water framework directive and the Danube River basin: Opportunities enhanced ecological management and public participation. European Water Management, 3(2), 46–50.