It wasnarrated that from 'Amr bin Shu'aib, from his father, from hisgrandfather, that the Messenger of Allah (ﷺ) said:
"Every prayerinwhich Fatihatil-Kitab (the Opening of the Book) is not recited, itisdeficient, it is deficient." (IT)
English reference (IT): Vol. 1, Book 5, Hadith 841 (IT)
Arabic reference (IT): Book 5, Hadith 890 (IT)