| URSUS | Frequency | EBSCO |
| - | irregular | **IR** |
| d | daily | **DS** **DA** |
| i | 3x week | |
| c | semi-weekly | **SW** |
| j | 3x month | |
| w | weekly | **WK** |
| e | biweekly | **BW** |
| s | semi-monthly | **SM** |
| m | monthly | **MO** |
| b | bimonthly | **BM** |
| q | quarterly | **QR** |
| t | 3x year | **TQ** |
| f | semi-annual | **SA** |
| a | annual | **AN** |
| g | biennial | **BE** |
| h | trienniel | **TE** |
| z | other | **OR** |
| u | unknown | **UN** |