/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String rx = "\\d+(?:,\\d+)?\\s*m\\u00B2";
		Pattern p = Pattern.compile(rx);
		Matcher matcher = p.matcher("E.g. : 4668,68 m² some text, some text 48 m²  etc");
		if (matcher.find()){
			System.out.println(matcher.group());
		}
	}
}

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