Before forming the union and being declared Khan on Khalkha Steppe in 1206, four tribes which Chinggis or Temujin subdued consequence of long toils were Kereyit, Naiman, Merkit Tatar tribes. Scientific Circle, unfortunately, is not still unanimous about ethnical involvement these language they spoke period Хамаг Монголын ханлиг. But, particularly, most names Kereyit Naiman are placed нууц товчо...

all that we know about the life and times of al-sijzī, the 10th century iranian muslim mathematician and astronomer, is limited to the small pieces of information provided by other authors’ accounts and some of his own works. on the basis of al-sijzī’s mathematical works and the extant maunscripts written in his hand, some modern scholars have estimated his date of birth in about 942 ad. numero...