Features of four different sources of occurrence data: 1) public collections, 2) private collections, 3) structured citizen science projects (i.e., projects where occurrences are combined into a single database), and 4) other observation data (e.g., scattered data from online sources).

 
  Part of: Giannini A, Oliverio M (2022) From Shells in House Cabinets to Structured Data for Research: The mobilization of frozen biodiversity data in Italy. Biodiversity Information Science and Standards 6: e93584. https://doi.org/10.3897/biss.6.93584