It is unclear whether the Avestan variation between "aṣ̌a" and "arta" is merely orthographical. Benveniste suggested "š" was only a convenient way of writing "rt" and should not be considered phonetically relevant. According to Gray, "ṣ̌" is a misreading, representing – not /ʃ/ - but /rr/, of uncertain phonetic value but "probably" representing a voiceless "r". Miller suggested that "rt" was restored when a scribe was aware of the morpheme boundary between the /r/ and /t/ (that is, whether the writer maintained the "–ta" suffix).