You should get this one organically but if not -
1. Start a Game With A Large Map, and Hard or Brutal Difficulty.
2. Click on the Laptop to Download Objectives.
3. If there is AT LEAST 2 Lorepages in your map, Run it until you find the lorepage.
(If Not See Step - 6)
4. Dont Open the Inner Tomb, That makes 1 of out 2 lorepages inaccessible BUT
5. Takes anywhere from 1 minute to 20 minutes to search the ruins. Collect the Lorepage (And/or Artifact) and
6. Run back out the the Jeep, And Close the Hatch.
7. Repeat Steps 1-6.
Takes a while but its not as big of a grind as you think, some maps have up to 4 lorepages so you can get 3 and boogy.
GL!