 In the Sassanian inscriptions, the formula "asp ud mard" (logographically spelled as Middle Persian SWSYA W GBRA and Parthian SWSYN W GBRYN; literally "horse and man") was commonly used to collectively refer to the cavalry and the infantry of the military.The aswaran were primarily composed of Iranian aristocrats from the "wuzurgan" and the "azadan", with members of the staff being from the former.After the reforms of Khosraw I, warriors from the "dehqan" class would also be enlisted.