Google
 
Trailing-Edge - PDP-10 Archives - BB-N593A-BB - dx20.dir
There are no other files named dx20.dir in the archive.

DX20	DIR     1  <055>   450314  17-Aug-82	DSKC:	[10,771,DX20]
DXMCD	ADX    16  <055>   450466   7-Aug-81
  Total of 17 blocks in 2 files Checksum = 447007 on DSKC: [10,771,DX20]