Newell-Hanson, Alice (12 April 2021). "Furry Friends: The Joy Ai Weiwei Gets From His Cats". As of June 30, 2021 (this selection is which includes the $40 million gift which was received prior to June 30, 2021 but selected later on as talked about on site 20). "California State University, Northridge Foundation Financial Statements (With Supplementary Information) and Independent Auditor's Report" (PDF). OECD. "Income distribution - Inequality".