Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_18 ( release_date VARCHAR, release_format VARCHAR, country VARCHAR )

### Question ###
What is the release date for the standard cd release format in north america?

### Accurate SQL ###

SELECT release_date FROM table_name_18 WHERE release_format = "standard cd" AND country = "north america"