"[T]o a lesser extent, {. . .] primary sources"  Your own quote states that primary sources are acceptable sources.  Without primary sources, there wouldn't 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 British/Imperial 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 aren't familiar with the system, can you explain to me why you feel qualified to edit it?

I wouldn't stick my neck out and get involved, say, in an article on women's 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?