Egyptian

Ariel Shisha-Halevy. 1976. The Circumstantial Present As An Antecedent-Less (I.e. Substantival) Relative In Coptic. Journal Of Egyptian Archaeology, 62, Pp. 134–137.
Coptic disposes of two procedures to express the substantival relative clause (‘he who…’, ‘that which…’ etc.), namely, either by substituting a substantivator morpheme (of the ⲡ-/ⲧ-/ⲛ- paradigm) for the antecedent, yet in close juncture with the relative-converted form: ⲡⲉⲧ-, ⲡⲉⲛⲧⲁϥ-, ⲡⲉϣⲁϥ-, etc.; or by having an indefinite pronoun or pronominal (ⲟⲩⲁ, ⲣⲱⲙⲉ, ϩⲟⲉⲓⲛⲉ: ‘one’, ‘any’, ‘some’) as antecedent to a circumstantially converted form, as the relative:circumstantial opposition is neutralized, in favour of the latter, when adnominal to a non-ⲡ-determined substantival kernel.[…]