There are 3 titles associated with this firm.

Richardson, Caroline E. Poems, By Mrs. G. G. Richardson, Dumfries. Edinburgh: Robert Cadell and Co. [41 St. Andrew Street], Simpkin, Marshall and Co., William Crofts, 1828.
Richardson, Caroline E. Poems, By Mrs. G. G. Richardson, Dumfries. Second edition. Edinburgh: Robert Cadell and Co. [41 St. Andrew Street], Simpkin, Marshall and Co., William Crofts, 1828.
Richardson, Caroline E. Poems by Mrs. G. G. Richardson. Second Series. London: Robert Cadell and Co. [31 St. Andrew Square 1830, 1833-1850], William Crofts, 1834.