Basic Formal Ontology

1. https://github.com/bfo-ontology/BFO/wiki
2. http://basic-formal-ontology.org/

BFO-2020

1. http://purl.obolibrary.org/obo/BFO_0000001 entity
   1. http://purl.obolibrary.org/obo/BFO_0000002 continuant
      1. http://purl.obolibrary.org/obo/BFO_0000004 independent continuant
         1. http://purl.obolibrary.org/obo/BFO_0000040 material entity
            1. http://purl.obolibrary.org/obo/BFO_0000024 fiat object part
            2. http://purl.obolibrary.org/obo/BFO_0000027 object aggregate
            3. http://purl.obolibrary.org/obo/BFO_0000030 object
         2. http://purl.obolibrary.org/obo/BFO_0000141 immaterial entity
            1. http://purl.obolibrary.org/obo/BFO_0000006 spatial region
               1. http://purl.obolibrary.org/obo/BFO_0000009 two-dimensional spatial region
               2. http://purl.obolibrary.org/obo/BFO_0000018 zero-dimensional spatial region
               3. http://purl.obolibrary.org/obo/BFO_0000026 one-dimensional spatial region
               4. http://purl.obolibrary.org/obo/BFO_0000028 three-dimensional spatial region
            2. http://purl.obolibrary.org/obo/BFO_0000029 site
            3. http://purl.obolibrary.org/obo/BFO_0000140 continuant fiat boundary
      2. http://purl.obolibrary.org/obo/BFO_0000020 specifically dependent continuant
      3. http://purl.obolibrary.org/obo/BFO_0000031 generically dependent continuant
   2. http://purl.obolibrary.org/obo/BFO_0000003 occurent
      1. http://purl.obolibrary.org/obo/BFO_0000008 temporal region
         1. http://purl.obolibrary.org/obo/BFO_0000038 one-dimensional temporal region
            1. github BFO hierarchy.png: temporal interval
         2. http://purl.obolibrary.org/obo/BFO_0000148 zero-dimensional temporal region
            1. github BFO hierarchy.png: temporal instant
      2. http://purl.obolibrary.org/obo/BFO_0000011 spatiotemporal region
      3. http://purl.obolibrary.org/obo/BFO_0000015 process
         1. http://purl.obolibrary.org/obo/BFO_0000144 process profile - not in github BFO hierarchy.png
         2. http://purl.obolibrary.org/obo/BFO_0000182 history
      4. http://purl.obolibrary.org/obo/BFO_0000035 process boundary

Release

https://ncorwiki.buffalo.edu/index.php/BFO_Release_History:_From_BFO_1_to_BFO-ISO

1. 2001 : BFO 1
2. 2007 : BFO 1.1
3. 2015 : BFO 2
   1. http://ncorwiki.buffalo.edu/index.php/Basic_Formal_Ontology_2.0
   2. http://ontology.buffalo.edu/bfo/BFO2.png
4. 2020 : BFO-2020

Third party text

BFO based ontology

1. https://www.sciencedirect.com/science/article/pii/S1877050919307380 - The Ontology of Systems Engineering: Towards a Computational Digital Engineering Semantic Framework

Fiat - Bona Fide

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3520998/ - Fiat or Bona Fide Boundary—A Matter of Granular Perspective