3ef8da02_Adhan_According_to_5_Schools__2
[0] Shafi’I [1] The Shafi'is do not consider it valid for janazah, mandhurah and nawafil prayers. [3] four times [4] twice [5] Twice [6] Twice [7] Twice [8] None [9] Twice [10] Once [11] it is mustahabb to recite iqamah before every daily obligatory salat, with the salat immediately following it. [12] Twice [13] Once [14] Once [15] Once [16] Once [17] None [18] Twice [19] Twice [20] Once [2] 
Adhan is valid even without niyyah. The other schools require niyyah. It is not valid for an Arab to make adhan in any other language, though it is valid for a non Arab to make it in his own tongue, for himself and his co-linguals.
Adhan According to 5 Schools
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