- L'Enfant, Pierre Charles, 1754-18252
- La Pérouse, Jean-François de Galaup, comte de, 1741-17882
- Lane, Alfred C. (Alfred Church), 1863-19482
- Langwith Publishing Company (Minneapolis, Minn.)2
- Lehr, J.D.2
- Lewis, J. Volney (Joseph Volney), 1869-19692
- Linant de Bellefonds, L.-M.-A. (Louis Maurice Adolphe), 1799-18832
- Lindsay, John F. (John Francis), 1941-20082
- Lipman, Louis2
- Little, R. L. (Geologist)2
- London Geographical Institute2
- Lotter, Tobias Conrad, 1717-17772
- Lucini, Antonio Francesco, 1605-2
- Lusardi, B.A2
- Lyne, James2
- Macomber, R. Z.2
- Mattke, Ryan2
- McSwiggen, Peter L.2
- Meints, Joyce P.2
- Michigan. Land Economic Survey2