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in this matter is the most popular phrase on the web.

on this matter 140,200,000 results on the web	in this matter 141,000,000 results on the web More popular!
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It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	I will respect the Avatar's wishes in this matter. The Council should take decisions in this matter after consultation of the European Parliament. I'm representing ADM in this matter. You seem to be representing everyone in this matter. Your opinion in this matter is very important, sir. I need you to be very clear in this matter. I really have no choice in this matter. Whatever options the President is or isn't considering in this matter are private.

on this matter

140,200,000 results on the web

in this matter

141,000,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

I will respect the Avatar's wishes in this matter.
The Council should take decisions in this matter after consultation of the European Parliament.
I'm representing ADM in this matter.
You seem to be representing everyone in this matter.
Your opinion in this matter is very important, sir.
I need you to be very clear in this matter.
I really have no choice in this matter.
Whatever options the President is or isn't considering in this matter are private.