Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Watanabe Aiko and Sakaguchi Hironobu,Song maintenance and plasticity in adult birds,Hikaku seiri seikagaku(Comparative Physiology and Biochemistry),09163786,THE JAPANESE SOCIETY FOR COMPARATIVE PHYSIOLOGY AND BIOCHEMISTRY,2006,23,1,20-31,https://cir.nii.ac.jp/crid/1390282679647071488,https://doi.org/10.3330/hikakuseiriseika.23.20