Can you recommend any good sources to explain how the Chinese government subsidises BYD? I’ve done a little bit of reading around and the term subsidy is often

Can you recommend any good sources to explain how the Chinese government subsidises BYD? I’ve done a little bit of reading around and the term subsidy is often used without further clarification. For example, is it direct payments, or business tax breaks, or tax breaks on sales of EVs, or something else?