From the publisher:
This file covers 13 Advanced Classes for the 1948 Campaign World. Some, like the Soldier, the Spy, and the Gentle Warrior, are gathered from other OGC sources and adjusted to fit the setting. Others, like the Research Scientist and the Machinist, are designed specifically for this release. Stop searching through a bunch of different books and PDFs to find the right Advanced Class for your 1948 hero. This file collects all the most common and relevant classes into one convenient location.
Includes the following Advanced Classes:
Combat Pilot
Demolition Expert
Field Medic
Gentle Warrior
Machinist
Martial Artist
Professional Driver
Research Scientist
Resistance Fighter
Sniper
Soldier
Spy
Survivalist