IAL - cannot use "CR"."OBJVERSION"

Hello,

I have following query in IAL:

SELECT
            pf.project_id
        FROM
                 &AO..contract_revision cr
            INNER JOIN &AO..sales_contract_cfv c ON cr.contract_no = c.contract_no
            INNER JOIN &AO..project_forecast   pf ON cf$_mci_project_id = pf.project_id

and WHERE:

      cr.objstate = 'Active'
            AND pf.forecast_type_id = 'BUD'
            AND pf.active_budget_db = 'TRUE'
            AND pf.latest_snapshot_date > TO_DATE(cr.objversion, 'YYYYMMDD HH24:MI:SS')

When save I have the error

cr.objversion ins not a valid object