A highly conserved repeated DNA element located in the chromosome of Streptococcus pneumoniae. - Bernard Martin; Odile Humbert; Miguel Cámara; Eric Guenzi; John Walker; Timothy Mitchell; Peter Andrew; Marc Prudhomme; Geneviève Alloing; Regine Hakenbeck; Donald A. Morrison; Graham J. Boulnois; et al. (Nucleic Acids Res., 1992)