[W.L., B. (1640). An helpe for yong people, preparing them for the worthy receiving of the Lords Supper. By W.L. B.D. Printed by T[homas] H[arper] for Nathaniel Butter at the Pyde Bull, neer St. Augustines Gate.
Chicago Style (17th ed.) Citation[W.L., B.D.]. An Helpe for Yong People, Preparing Them for the Worthy Receiving of the Lords Supper. By W.L. B.D. Londn [sic]: Printed by T[homas] H[arper] for Nathaniel Butter at the Pyde Bull, neer St. Augustines Gate, 1640.
MLA (9th ed.) Citation[W.L., B.D.]. An Helpe for Yong People, Preparing Them for the Worthy Receiving of the Lords Supper. By W.L. B.D. Printed by T[homas] H[arper] for Nathaniel Butter at the Pyde Bull, neer St. Augustines Gate, 1640.
Warning: These citations may not always be 100% accurate.