| Rule Description | Element Content |
|---|---|
| EMPTY | No children allowed |
| (E*) | Any sequence of 0 or more elements E |
| (E+) | Any sequence of 1 or more elements E |
| (E?) | Optional element E (0 or 1) |
| (E1, E2, . . .) | Element E1, followed by E2, ... |
| (E1|E2|. . .) | Element E1 or E2 or ... |
| (#PCDATA) | Text only (parsable) |
| (#PCDATA|E1|E2|. . .)* | Any sequence of text and elements E1, E2, ..., in any order |
| ANY | Any children allowed |