how to prevent all_tab_columns/col from selecting external tables

Oracle 11.2.0.4 (Standard Edition)

how to prevent all_tab_columns/col from selecting external tables? Documnetation does not mention this.

I'm assuming there is no way except for

SELECT distinct owner, table_name

FROM all_tab_columns

WHERE owner = 'EIS_REPORT' and table_name NOT IN (SELECT TABLE_NAME FROM ALL_EXTERNAL_TABLES)

order by table_name;

or

SELECT distinct owner, table_name

FROM all_tab_columns

WHERE owner = 'EIS_REPORT' and table_name NOT EXISTS (SELECT 42 FROM ALL_EXTERNAL_TABLES WHERE ALL_TAB_COLUMNS.TABLE_NAME = ALL_EXTERNAL.TABLE_NAME)

order by table_name;

for second query, thank you to a_horse_with_no_name from stack overflow for where I got it from.