Oracle Materialized View Refresh Group - Montly Interval

I have a few Materialized Views that I need to update weekly and monthly.

So for the weekly I'm using:

Code:

---

execute DBMS_REFRESH.MAKE(
name=>'LPMVRefresh_Weekly_1',
list=>'mySchema.MV1_mv,mySchema.MV2_mv',
next_date => TO_DATE('2013-09-08:00:30:00','YYYY-MM-DD:HH24:MI:SS'),
interval =>'sysdate+7');

---

How can I do so they refresh monthly, say every 1st of the month at 1 am? Is there something like Interval => sysdate+monthly?

I have not used the DBMS_REFRESH.MAKE method, however, this will get you the next 1AM on the first of the month.

SYS@rdbadb01 AS SYSDBA> select to_char(add_months(trunc(sysdate, 'MM'), 1)+1/24, 'DD-MON-YYYY:HH24:MI:SS') next_date from dual;

NEXT_DATE
---------------------------------------------------------------------------------------
01-OCT-2013:01:00:00

Elapsed: 00:00:00.05

Thanks,