Names
- Lamb, Thos. W. (Thomas White), 1871-19421
- Leeds Fireclay Co1
- Lehman, William E.1
- Levitan, Benjamin W., 1878-19411
- Ludlow & Peabody1
- Lyons, Robert T1
- Marshall & Fox (Firm)1
- Maryland Terra Cotta Co1
- Maynicke & Franke1
- McKenzie, Voorhees & Gmelin1
- McKim, Mead & White1
- Merchant, Alexander1
- Meyers, Charles B1
- Midland Terra Cotta Co1
- Milburn, Heister & Co1
- Mills, Rhines, Bellman & Nordhoff, Architects1
- Moore & Landsiedel1
- Morris, Montrose W., 1861-19161
- Mowbray & Uffinger1
- Murphy & Olmsted1