<Tr> <Td> </Td> <Td> </Td> <Td> </Td> <Td> 3rd Fighter Air Corps </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> </Td> <Td> 7th Fighter Air Corps </Td> <Td> </Td> </Tr> <Table> <Tr> <Th> Operation Citadel </Th> <Th_colspan="3"> Men </Th> <Th_colspan="3"> Tanks </Th> <Th_colspan="3"> Guns </Th> </Tr> <Tr> <Th> Soviet </Th> <Th> Ratio </Th> <Th> German </Th> <Th> Soviet </Th> <Th> Ratio </Th> <Th> German </Th> <Th> Soviet </Th> <Th> Ratio </Th> <Th> German </Th> </Tr> <Tr> <Th> Frieser </Th> <Td> 1,426,352 </Td> <Td> 2.8: 1 </Td> <Td> 518,271 </Td> <Td> 4,938 </Td> <Td> 2: 1 </Td> <Td> 2,465 </Td> <Td> 31,415 </Td> <Td> 4: 1 </Td> <Td> 7,417 </Td> </Tr> <Tr> <Th> Glantz </Th> <Td> 1,910,361 </Td> <Td> 2.5: 1 </Td> <Td> 780,900 </Td> <Td> 5,128 </Td> <Td> 1.7: 1 </Td> <Td> 2,928 </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td_colspan="11"> <Ol> <Li> Jump up ^ Frieser uses combat strengths . </Li> <Li> Jump up ^ Frieser counts only operational tanks . </Li> <Li> Jump up ^ Glantz uses total strengths . </Li> </Ol> </Td> </Tr> </Table> <Tr> <Th> Operation Citadel </Th> <Th_colspan="3"> Men </Th> <Th_colspan="3"> Tanks </Th> <Th_colspan="3"> Guns </Th> </Tr>

Where did the largest and bloodiest battle take place in the second world war