| 1961 MAGNUS Chord Type Reed Organ Patent Print |
| 1935 MCFARLAN Piano Chord Player Patent Print |
| 1971 HALPIN Chord Construction Guide Patent 25789 |
| 1962 CAREY PHILIP MFG CO Chord Chime Patent |
| 1954 MARIO MACCAFERRI Chord Player Patent Print |
| 1962 RINKER CARL Chord Chime Patent Print Art |
| 1967 WEIS Music Chord Finder Device Patent Print |
| 1968 ERNEST Foot Operated Chord Organ Patent |
| 1965 ULRICH Chord Tuning Mechanism Patent 21387 |
| 1957 HAYES Chord Playing Attachment Patent Print |
| 1953 RUBEN Chord Playing Harmonica Patent Print |
| 1962 LO Key Arrangements For Chord Organs Patent |
| 1957 JONES Changeable Chord Finder Patent Print |
| 1965 VON Piano Having Chord Playing Means Patent |
| 1956 SMIT Chord Changing Device Patent Print Art |
| 1960 STANLEY CUTLER Chord Organ Patent Print Art |
| 1961 LO Keyboard For Chord Organ Patent Print |
| 1957 JONES Simple Changeable Chord Finder Patent 25678 |
| 1931 RAYMOND CORDIER Chord Finder Patent Print |
| 1962 CZARNECKI ELI Chord Organ Patent Print Art |
| 1958 SLEEMAN WILLIAM Car Top Chord Patent Print |
| 1961 MCGINLEY Musical Chord Chart Patent Print |
| 1939 GLENN L MARTIN CO Spar Chord Patent Print |