Overview of MESINESP, a Spanish Medical Semantic Indexing Task within BioASQ 2020. - Carlos Rodríguez Penagos; Anastasios Nentidis; Aitor Gonzalez-Agirre; Alejandro Asensio; Jordi Armengol-Estapé; Anastasia Krithara; Marta Villegas; Georgios Paliouras; Martin Krallinger (CLEF (Working Notes), 2020)