Legislation in force (for example, Federal law «On accounting», Tax and Civil Codes) stipulate generation of documents in paper as well as in electronic form. And it is not stated that paper copy is binding. If upon agreement of the parties a document was transferred via telecommunication channels, signed with digital e-signature, it is an original. All documents stated in Diadoc Rules may be transferred in e-form, without duplicating on paper, including invoices (since May, 23th 2012, when Order of FNS of Russia dated March, 5th 2012 № ММВ-7-6/138 comes in force).