can I transit without visa

Hello I'm a Colombian national studying for Sorbonne University in Paris - France. I bought my tickets round trip to go to Hong Kong in July, but has a short (3 hours) stop in Beijing due that's by "Chinese Southern Airlines". Do I need a transit G type? I read in the embassy website that for a transit to a 3rd country, having all documents correctly and leaving PRC before the 24h is not necessary any entry permit. Thanks for your soon information