Imperative.—In the third person singular the perfect meaning is regularly retained, as εἰρήσθω
a. The dual and 3 pl. are apparently wanting. The 2 sing. in -νσο from stems in -ν does not occur. For πέφανσο, πεφασμένος ἴσθι was probably used.
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].