I used the construction depth reference manual, not a ton but it helped. I spent more time looking up info in references I had while studying, to later find out a lot of it is actually in the Construction Depth reference manual. If you learn that manual well and know the sections that are actually covered in it, it can save you from needing a few of the other references listed for Construction Depth. It covers shoring, temporary loads on structures, trench/retaining wall design/geotech, accounting, estimating, and a lot of other stuff. Great overall afternoon reference if you learn how to use it, I could have saved time and money if I had studied more of it and realized I didn't need a few other books I bought.