NORTHERN ILLINOIS GAS CO /IL/ /NEW/ 10-Q

NICOR GAS FORM 10-Q 09-30-11

NICOR GAS EXHIBIT 12.01 RATIO OF EARNINGS TO FIXED CHARGES

NICOR GAS EXHIBIT 31.01 CERTIFICATION

NICOR GAS EXHIBIT 31.02 CERTIFICATION

NICOR GAS EXHIBIT 32.01 CERTIFICATION

NICOR GAS EXHIBIT 32.02 CERTIFICATION

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