Any Scholars whose rules are in accordance with Quran and the right sunnah ( rules ) that were narrated about Prophet Mohammed (pbuh). They do not based their rules on their desires or to satisfy people.
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They did not know that earth is round <--- apex!
Much was preserved by the Islamic medieval Islamic scholars.
Arabic
ulema
Numerous people, typically Islamic Scholars and researchers into Islam and its traditions.
The caliphs/emirs/sultans and the scholars and judges
One of the leaders of Mali, Mansa Musa, was Islamic so he tried making Mali islamic. On his journey home to west africa, Mansa Musa brought with him several Islamic scholars to teach his people the words of Qu'ran and just how to live as true muslims.
The Muslim scholars formulated trade and economic rules and provided guidance in the field of trade and economics.
islamic public school
Most scholars (both Islamic and Non-Islamic) believe a lunar or luni-solar calendar was in existence in pre-Islamic Arabia, with the obvious omission of the four 'special' months.
Islamic sources are mainly Quran(holy book of Muslims),Sunnah(practices of prophet Muhammad SAW) and Hadith(Sayings of prophet Muhammad SAW) and some other Islamic literature written by Muslim scholars.
Muslim scholars not only studied and made advances in the field of Mathematics, Algebra, Geometry, rather they did lot of research in the field of medicine and all branches of science.
Musa traveled to the city of Baghdad to gather scholars for his court. Baghdad was known as a center of learning, culture, and intellectual pursuits during the height of the Islamic Golden Age.