There are 6 titles associated with this firm.

Manley, Delarivier. The lost lover; or, the jealous husband: a comedy. As it is acted at the Theatre Royal by His Majesty’s Servants. Written by Mrs. Manley. London: Francis Saunders, Richard Bentley, James Knapton, Richard Wellington I, 1698.
de Guilleragues, Gabriel-Joseph. Five love-letters from a nun to a cavalier. Done out of French into English, by Sir Roger L'Estrange. The Second Edition. London: Richard Wellington I, Elizabeth Rumball, 1701.