Before revision: Planetary surface construction can be divided into three phases or classes, coinciding with a phased schedule for habitation (Kennedy 2002, Smith 1993 ): • Class I: Pre-integrated hard shell modules ready to use immediately upon delivery.
After revision: Planetary surface construction can be divided into three phases or classes, coinciding with a phased schedule for habitation :Kennedy 2002Smith 1993 • Class I: Pre-integrated hard shell modules ready to use immediately upon delivery.