This is a variant on what appears on your leaflets, and is also mandatory for websites.
The imprint needs the name and contact address (NB Not NECESSARILY Home Address, but also not an e-mail or PO Box Number, it must be a physical address) of the person who would get sued if there was a problem.For sites controlled by the central party, including content:
Promoted by Tony McIntyre on behalf of UKIP, Lexdrum House, King Charles Business Park, Newton Abbot, Devon TQ12 6UT. Copyright © (start date) - 2018.Official Guidance:
More infirmation from the Electoral Commission can be found here.