7 mm continuum observations of ultra compact HII regions P. Leto, G. Umana, C. Trigilio, C. S. Buemi, S. Dolei, P. Manzitto, L. Cerrigone and C. Siringo A&A, 507 3 (2009) 1467-1473 Published online: 01 October 2009 DOI: 10.1051/0004-6361/200911894