https://academic.oup.com/cid/article/34/Supplement_2/S58/459...
> In summary, the present evidence indicates that the H5N1 strains that caused the Hong Kong 1997 outbreak were reassortants from multiple cocirculating avian influenza virus strains
https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC3323155/
> On January 2, 2003, two cases of atypical pneumonia in the city of Heyuan, Guangdong Province, were associated with transmission of infection to several healthcare workers at the hospital (5). Investigation by the Guangdong Provincial Center for Disease Control and Prevention led to the identification of clusters of cases in six other municipalities (Foshan, Jiangmen, Zhongshan, Guangzhou, Shenzhen, Zhaoqing) from November 2002 to mid-January 2003.
I literally took the first two papers I found via googling.
> the wet market theory has a reasonably credible history.
You're free to cite some of this history.