TMS320F28P650DK: ADC configuration

Hi Team,

My customer ask us the configuration of ADCs. They consider to use ADC-A and ADC-B with internal reference, and not to use ADC-C. For this case, customer needs to connect VREFHIB to A, and VREFLOB to A, but how should they do for VREFHIC and VREFLOC? Also if there is any other things they need to care, please let me know.

Thanks,
Nobuhiko Wasa