Wad found by Jive in "dmwad01.zip", collection downloadable here:
http://www.filelibrary.com/Contents/DOS/104/40.html
Release date: December 06, 1994

===========================================================
     MAXIMUM DOOM COLLECTION: DOOM WAD FILES (1,629)
===========================================================
Release Date in "The Master Levels for Doom" 
(CD-ROM which contains 2 map collections: "The Master Levels" and "Maximum Doom"):

APOCALY WAD 1,587,254  12-05-94  1:17p APOCALY.WAD

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This document must be viewed with a fixed width font (as "Courier new")
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      Revised on June 26, 2002 by Jean-Yves Delpech, aka "Jive"

(No fondamental modifications of the levels!)

(Mistakes rectification, Missing textures research and addition with :
       "WinDEU32" version 5.99b1 BCC by the "DEU team":
Renaud Paquay, Raphael Quinet, Brendon Wyber, Ted Vessenes and others.)

(PWAD examination with "Wintex" ver 4.7 (A WAD Editor Copyright (c) 1995-2002) 
       Olivier Montanuy  montanuy@inf.enst.fr
       Javier Almenara   aojavierfdo@hotmail.com
                         jao2000@evangelion.com
              WEB Pages: http://doortohell.tripod.com
                         http://www.geocities.com/locusfocus

(Nodes reconstruction with :
      -"Zennode.exe" (Ver 1.1.0, from Marc Rousseau)
            rousseaum@pictel.com
            http://www.mrousseau.org/programs/ZenNode/

(Pwad reconstruction with "Wadman.exe" ver 1.03, de Carl W. Moore)
       (Sysop: The Cutting Edge BBS  (505)-479-4064)
	 
(Graphic's creation or modification
      - Paint Shop Pro 7 (WinShare Killer Apps)
        http://www.wska.com

#########################################################################
 #  Author   : Jean-Yves Delpech aka "Jive" aka "Le freeman", 48 ans   #
 #  Email    : dlw@doomwadstation.com                                  #
 #  Web site : "Doom Legacy Wads" aka DLW                              #
 #             http://doomwadstation.com/dlw/                          #
#########################################################################
                    Where to get Doom Legacy :
#########################################################################
 #    e-mail: hurdler@newdoom.com  (Thierry Van Elsuwe)                #
 #            bpereira@newdoom.com (Boris Pereira)                     #
 #                                                                     #
 #  Web site: http://legacy.newdoom.com/                               #
 #    e-mail: legacy@newdoom.com                                       #
#########################################################################
 # Special thanks to Steven McGranahan, Robert Bäuml and Bell Kin for  #
 #  their large contribution and to others Legacy Team members.        #
#########################################################################

Updated by Jive, July 07, 2002:

- Added entries "P_START" & "P_END" in wad file.
- E1M3: Flipped & added action 195 (teleport exit when pressed) on linedefs
          655, 656 & 657 to avoid trap in sector 11.
        Flipped linedef 772 (open door)
        Changed height sector 153 (80-->64) to have a best texture display.
        Aligned textures sector 136.
- E1M9: Added missing upper texture on linedefs 854 & 861, second sidedefs.
        Aligned sector 189 on editor grid line.
- E1M4: Added action 45 (lower floor) on linedef 1746 to allow sector 419 bypass.
- E1M6: Added missing lower textures on linedefs 834 to 837.

E1M1: HELL ON IO, missions 1-4 (E1M1), by Daniel Hornbaker (April 1994)
      Map28 in "Newdoom2.wad", converted megawad (compiled by Jive, December 12, 1999)
E1M2: HELL ON IO, missions 1-4 (E1M2)
      Map29 in "Newdoom2.wad"
E1M3: HELL ON IO, missions 1-4 (E1M3)
      Map30 in "Newdoom2.wad"
E1M9: HELL ON IO, missions 1-4 (E1M4)
      Map31 in "Newdoom2.wad"