I want to know the answer to the following question:
Who has claimed that Christians and Jews had heard and discussed the Quran before it took on its standardized Arabic form?
All the background I'm provided with is that "According to Sahih al-Bukhari, the Quran was recited among Levantines and Iraqis, and discussed by Christians and Jews, before it was standardized.". Is that enough to answer the question?