More weird AAP stuff: the lunar landing Skylab

This sketch shows another weird draft from the Apollo Applications Program. It is an early design of Skylab - but note the lunar lander attached! Apparently it was not meant to land, though, but to host crew members operating the ATM.

The numbers signify:
1. "Workshop" (a modified hydrogen tank of an S-4B stage) for crew adaption and microgravity experiment purposes
2. Node adapter and hatch
3. Apollo CSM
4. M&SS - Mapping and Space Research System
5. LEM with attached Apollo Telescope Module (ATM)