Building Open-Retrieval Conversational Question Answering Systems by Generating Synthetic Data and Decontextualizing User Questions. - Christos Vlachos; Nikolaos Stylianou; Alexandra Fiotaki; Spiros Methenitis; Elisavet Palogiannidi; Themos Stafylakis; Ion Androutsopoulos (CoRR, 2025)