BUENOS AIRES - The Argentine couple Agustina Vignau and Hugo Mastrolorenzo won the stage category of the World Tango Championship in Buenos Aires on Wednesday, dancing to a classic ballad by Astor Piazzolla. “Every year, the world (championship) makes us grow a lot,” Vignau said. “One celebrates the process because if we had won before, we would not have created everything we do.” Unlike the more formal salon category, the stage category is more acrobatic and choreographic. Of the 19 couples in the final at the Luna Park stadium, eleven were from Argentina, three from Russia, three from Colombia, one from Brazil and one from Italy. Members of the the public could vote for their favorite dancers via the internet for the first time during the final, with some 13,000 people participating, organizers said.