Conversation so far:
when did Winnie Madikizela-Mandela die?
Winnie Madikizela-Mandela died at the Netcare Milpark Hospital in Johannesburg on 2 April 2018.
how did she die?
She suffered from diabetes and had recently undergone several major surgeries.
When was her funeral?
Her public funeral service was held at Orlando Stadium on 14 April 2018.

Question: Where was she buried?
Self-contained rewrite: Where was Winnie Madikzela Mandela buried?