UTRdb and UTRsite: a collection of sequences and regulatory motifs of the untranslated regions of eukaryotic mRNAs. - Flavio Mignone; Giorgio Grillo; Flavio Licciulli; Michele Iacono; Sabino Liuni; Paul J. Kersey; Jorge Duarte; Cecilia Saccone; Graziano Pesole (Nucleic Acids Res., 2005)