To a lesser extent    primary sources  Your own quote states that primary sources are acceptable sources  Without primary sources there wouldnt be any secondary sources to quote  How can you read the same exact page and not discern its meaning  I am starting to become very annoyed at these incessant reversions  Do you have a personal bias here  In Sri Lanka an old system of measurement is used for land The Perch and Rood are old BritishImperial measurement systems  From the realtor page  It clearly states that the perch and rood are old Imperial measurement systems and that in Sri Lanka they use an old system the Imperial measurement system  If you arent familiar with the system can you explain to me why you feel qualified to edit it   I wouldnt stick my neck out and get involved say in an article on womens fashion  Yet you feel qualified to summarily delete changes made in good faith citing reliable primary sources from the countries in question  Are you serious in saying that someone needs to read the SAME INFORMATION WRITE A BOOK ABOUT IT before I can cite it here