Trident I C-4 FBM / SLBM

References

• "A History of the FBM System" by Lockheed Missiles and Space Company, Inc.
  
• "TRIDENT I (C4) development - 1980" by VADM Levering Smith (ret) formerly SP-00, RADM Robert H. Wertheim SP-00, and Robert A. Duffy, President of Charles Stark Draper Laboratory.