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_8 (width_feet__m_ VARCHAR, source__year_ VARCHAR)

### Question ###
What is the width for hte truss with a source of zacher (1994)?

### Accurate SQL ###

SELECT width_feet__m_ FROM table_name_8 WHERE source__year_ = "zacher (1994)"