This page contains the links to the articles describing the processes that Agisoft Metashape uses and is basing on. Although, definitely, Metashape includes a number of optimizations, that are a part of the company know-how. 

1. Build DEM using Depth Map - Thomas Pock, Lukas Fusion, and Horst Bischof: TGV-Fusion

2. The base principles of the ground points classification method applied in Metashape Pro are described in the following scientific paper - Peter Axelsson: DEM Generation from Laser scanner data using adaptive TIN models

3. Classify Points (multi-class classification) - C. Becker, N. Hani, E. Rosinskaya, E. d'Angelo, C. Strecha: Classification of aerial photogrammetric 3D point clouds

4. Heiko Hirschmuller: Stereo Processing by Semi-Global Matching and Mutual Information (2007)

5. Recommended MicaSense image processing technique - MicaSense RedEdge Image Processing Tutorial