Reasons for altering the new duty of thirty per cent. ad valorem upon books imported to a duty of twelve shillings per hundred weight, humbly offer'd to the Honourable House of Commons [electronic resource].
Apparently refers to the 1712 Act (10 Anne c.19) imposing a duty of 30% ad valorum on imported books & the 1714 Act (12 Anne c.9) increasing the duty on imported paper. Reproduction of original from the University of London's Goldsmiths' Library. Available online to authorized PSU users as part of the Social sciences and fine arts series of Eighteenth century collections online.
Electronic reproduction. Farmington Hills, Mich. : Thomson Gale, 2003. Available via the World Wide Web. Access limited by licensing agreements
Hanson, 1917 English Short Title Catalog, ESTCN6143.