Function interface_transfer_checked_signed 

pub fn interface_transfer_checked_signed<'a>(
    source: &'a AccountView,
    mint: &'a AccountView,
    destination: &'a AccountView,
    authority: &'a AccountView,
    amount: u64,
    decimals: u8,
    signers: &[Signer<'_, '_>],
) -> Result<(), ProgramError>

PDA-signing variant of interface_transfer_checked.