Fast http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.60.3991&rep=rep1&type=pdf
Orb http://www.gwylab.com/download/ORB_2012.pdf
Dense VO https://ieeexplore.ieee.org/document/6631104
Imu Preintgration http://rpg.ifi.uzh.ch/docs/TRO16_forster.pdf
Sparse Bundle Adjustment http://users.ics.forth.gr/~lourakis/sba/sba-toms.pdf
Inverse Depth Parameterization https://www.doc.ic.ac.uk/~ajd/Publications/civera_etal_tro2008.pdf
8 Point https://www.cse.unr.edu/~bebis/CS485/Handouts/hartley.pdf
5 Point - https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.61.9329&rep=rep1&type=pdf
Rotation Coordinate Descent - https://arxiv.org/abs/2103.08292