found: His To the Right Hon'ble The Master, wardens, and assistants of the Corporation of Trinity House of Deptford Strond, this chart of the English Channel, 1830?:map recto (Rich'd Holmes Laurie)
found: Tooley's dict. mapmakers, 1979(Laurie, Richard Holmes, fl. 1822-1858, chartseller to Admiralty)
found: Oxford DNB online, 31 July 2013:under entry for his father Robert Laurie (Richard Holmes Laurie, died 19 January 1858 in London)
found: British Museum website, 31 July 2013:collection database, biogs., under Robert Sayer (when Sayer's health failed in 1792 his assistants Robert Laurie and James Whittle took over the management of his company; from Sayer's death in 1794 until Laurie's retirement in 1812, the company traded as "Laurie & Whittle"; from 1812 until his death in 1818, Whittle traded with Laurie's son, Richard Holmes Laurie, as "Whittle and Laurie")