Mattar J. Distance learning, emergency remote teaching and blended learning: research methodologies. In: Visiones en educación sin barreras ni fronteras: Un homenaje al Maestro Lorenzo García Aretio [Internet]. Colombia,CO: Sello Editorial UNAD; 2021 [cited 2025 Aug. 4]. pp. 30-7. (Institucional). Available from: https://libros.unad.edu.co/index.php/selloeditorial/catalog/book/109/chapter/961