TM 5-805-4/AFJMAN 32-1090
ELEVATION
Part A. Reflection From a Wall Behind the Barrier
ELEVATION
Part B. Reflection From Trees Over the Top of the Barrier 
Part C. Reflection From Trees or Other Structures Around 
the Ends of the Barrier
Figure 5-7. Examples of Surfaces That Can Reflect Sound Around or Over a Barrier Wall.
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