Question: Did the Prophet begin his dua (after salah, and at any other occasion) with the word:SUBHANAA RABBIYAL ALIYYIL ALEL WAHAAB. I found a hadeeth in Musnad Ahmed bin Hanbel 4/ 54 which is saying so. Is this SAHEEH?
Answer: The correct phrase is SUBHAANA RABBIYA-L-'A^LA-L-WAHHAAB. It is mentioned in Musnad Ahmad as a phrase used to start a supplication. I do not know the rank ofthe hadith, but there is no harm in using this phrase.
... and Allah knows best.