found: John Langdon, 1986: t.p. (John Langdon) p. 7 (b. 6/26/1741; d. 9/18/1819)
found: LC data base, 9-12-86 (hdg.: Langdon, John, 1741-1819)
found: New Hampshire. President (1785-1786 : Langdon). By His Excellency John Langdon, Esquire, president of the state of New-Hampshire a proclamation, 1785.
found: New Hampshire. President (1788-1789 : Langdon). By His Excellency John Langdon, Esquire, captain-general and commander in chief in and over the state of New Hampshire. A proclamation, 1788.
found: Raimo, J.W. Biog. dir. of Amer. colonial and revolutionary governors 1607-1789, 1980: (Langdon, John; N.H. president 1785-86 and 1788-89)
found: NUCMC data from New Hampshire Hist. Soc. for His Papers, 1762-1972 (John Langdon; served as governor of New Hampshire, 1805-1809)
found: American leaders 1789-1994, c1994: p. 441 (John Langdon; N.H. gov., June 6, 1805-June 8, 1809 and June 7, 1810-June 5, 1812)