Bolufer P, Lo Coco F, Grimwade D, Barragan E, Diverio D, Cassinat B, Chomienne C, Gonzalez M, Colomer D, Gomez M, Marugan I, Roman J, Delgado M, Garcia-Marco J, Bornstein R, Vizmanos J, Martinez B, Jansen J, Villegas A, de Blas J, Cabello P, Sanz M. Variability in the levels of PML-RAR alpha fusion transcripts detected by the laboratories participating in an external quality control program using several reverse transcription polymerase chain reaction protocols. Haematologica 2001; 86(6):570-576.