Drop-head title. First line of text: "I. Excerpta quædam e Newtoni principiis". Dated on internal evidence. Reproduction of original from the British Library. Available online to authorized PSU users as part of the General reference 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