title: Simultaneous determination of phosphate and silicate by first-derivative spectrophotometry.
authors.affiliation: Department of Chemistry, Faculty of Science, Al-Azhar University, Assiut, Egypt.
authors.forename: A A
authors.initials: AA
authors.lastname: El-Sayed
authors.forename: Y Z
authors.initials: YZ
authors.lastname: Hussein
authors.forename: M A
authors.initials: MA
authors.lastname: Mohammed