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_51999 ( "Date of Issue" text, "Denomination" text, "Design" text, "Paper Type" text, "First Day Cover Cancellation" text )

### Question ###
What is the paper type that the one that was issued on 26 july 2007 done on?

### Accurate SQL ###

SELECT "Paper Type" FROM table_51999 WHERE "Date of Issue" = '26 july 2007'