Probing long-period companions to planetary hosts - VLT and CFHT near infrared coronographic imaging surveysG. Chauvin, A.-M. Lagrange, S. Udry, T. Fusco, F. Galland, D. Naef, J.-L. Beuzit and M. MayorA&A, 456 3 (2006) 1165-1172DOI: https://doi.org/10.1051/0004-6361:20054709