Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Types of documents published from 2000 to 2020.
| Documents type | NR | Percentage (%) |
|---|---|---|
| Article | 4326 | 60.78 |
| Review | 2366 | 33.24 |
| Meeting abstract | 181 | 2.54 |
| Proceedings paper | 180 | 2.53 |
| Editorial material | 138 | 1.94 |
| Book chapter | 85 | 1.19 |
| Letter | 39 | 0.55 |
| Correction | 10 | 0.14 |
| Data paper | 7 | 0.10 |
| Early access | 6 | 0.08 |
| News item | 6 | 0.08 |
| Retracted publication | 4 | 0.06 |
| Biographical item | 1 | 0.01 |
NR: number of published documents.
