The recording sessions from the soraUVALAL corpus took place at the schools the participants attended in the country where they lived (i.e., Spain, Denmark and Bosnia).

In the recordings we followed the procedure specified in the literature on monolingual and bilingual acquisition (e.g., Slobin 1985, De Houwer 1990, López Ornat 1994, McDaniel et al. 1995, Thornton 1996, Rice et al. 1999, Bel 2001).

Before doing the tests, warming-up sessions were conducted so that participants were familiar with both the researcher and the rationale of the tests.

The transcriptions of the recordings in the soraUVALAL corpus were codified in the CHAT system for the TalkBank project (MacWhinney 2019).

Inventory: information for each session (MLUw, number of utterances, etc.).

CHAT format: information regarding the transcription procedure (headers, codes, etc.).