@article{GT_2021_25_3_a1,
     author = {Freed, Daniel S and Hopkins, Michael J},
     title = {Reflection positivity and invertible topological phases},
     journal = {Geometry & topology},
     pages = {1165--1330},
     publisher = {mathdoc},
     volume = {25},
     number = {3},
     year = {2021},
     doi = {10.2140/gt.2021.25.1165},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/gt.2021.25.1165/}
}