Rossi, Michele
Terracini, Lea
Article History
Received: 14 May 2015
Accepted: 16 April 2016
First Online: 2 May 2016
Change Date: 21 September 2017
Change Type: Erratum
Change Details: After the publication of [2], we realized that Proposition 3.1, in that paper, contains an error, whose consequences are rather pervasive along the whole section 3 and for some aspects of examples 5.1 and 5.2. Here we give a complete account of needed corrections.