Errors of blocks that i deleted

Hi guys,

I keep on getting errors of blocks that i deleted since i installed this module.

They are: [XXXX1 & 2] was blocks i deleted.

Notice: Undefined index: XXXXX1 in _blockreference_potential_references_standard() (line 497 of sites\all\modules\blockreference\blockreference.module).
Notice: Undefined index: in _blockreference_potential_references_standard() (line 497 of sites\all\modules\blockreference\blockreference.module). <--- not sure what this is - got this error from the start.
Notice: Undefined index: XXXXX2 in _blockreference_potential_references_standard() (line 497 of sites\all\modules\blockreference\blockreference.module).

Any help would be appreciated thanks