How can I print Proposal reference no and its date on the Invoice

Is it possible to print the Proposal reference number and its date on the Invoice odt template?

Secondly, whenever I generate the using doc odt template, I am getting the following Warning

Warning : md5_file(c:/dolibarr/dolibarr_documents/propale/(PROV8)/(PROV8).odt): failed to open stream: No such file or directory in C:\dolibarr\www\dolibarr\htdocs\core\class\commonobject.class.php on line 5419