Proto-Germanic: *ja (see there for further descendants)
Hellenic:
Ancient Greek: ἴα(ía) (Hom.f. "one", from *íh₂), εἰ(ei), ἐπεί(epeí), εἶτα(eîta), εἴθε(eíthe), ἔνθα(éntha), ἔνθεν(énthen)
Indo-Iranian:
Sanskrit: अतस्(átas), अथ(átha), अथा(áthā), अद्धा(addhā́), अध(ádha), अह(áha), अधा(ádhā), आद्(ā́d), इतस्(itás), इदा(idā́), ईम्(īm), एतद्(etad) (see there for further descendants)
^ Sihler, Andrew L. (1995) New Comparative Grammar of Greek and Latin, Oxford, New York: Oxford University Press, →ISBN, page 391
^ Ringe, Donald (2006) From Proto-Indo-European to Proto-Germanic (A Linguistic History of English; 1)[1], Oxford: Oxford University Press, →ISBN, page 56f
^ Beekes, Robert S. P. (2011) Comparative Indo-European Linguistics: An Introduction, 2nd edition, revised and corrected by Michiel de Vaan, Amsterdam, Philadelphia: John Benjamins Publishing Company, pages 227–229
^ De Vaan, Michiel (2008) “cēterus”, in Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill, →ISBN
^ Dunkel, George E. (2014) “*e- 'besagter, der erwähnte'”, in Lexikon der indogermanischen Partikeln und Pronominalstämme [Lexicon of Indo-European Particles and Pronominal Stems] (in German), volume 2: Lexikon, Heidelberg: Universitätsverlag Winter, →ISBN, pages 183-198
^ Derksen, Rick (2008) “*eterъ”, in Etymological Dictionary of the Slavic Inherited Lexicon (Leiden Indo-European Etymological Dictionary Series; 4), Leiden, Boston: Brill, →ISBN, page 147
^ De Vaan, Michiel (2008) “iterum”, in Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill, →ISBN, pages 311-312
^ Lubotsky, Alexander (2011) “íti”, in The Indo-Aryan Inherited Lexicon (in progress) (Indo-European Etymological Dictionary Project), Leiden University, page 236