[NTG-context] Bold italic font in Math (\definefallbackfamily)

Hello list, What is correct way to set bold italic font in math? \definefontfamily [Mainface] [rm] [Minion Pro] \definefallbackfamily [Mainface] [mm] [Minion Pro] [preset=math:lowercaseitalic] \definefontfamily [Mainface] [mm] [TeX Gyre Pagella Math] \setupbodyfont[Mainface] \starttext \startformula abc123 \stopformula \stoptext Thanks.