This is a petition for review of a decision of the National Labor Relations Board and cross-petition by the Board *8 for enforcement of its order. Petitioner . admits it has refused to bargain with a certified union but contends the union certification was based on an invalid election. The Board refused to consider this contention as untimely and summarily entered its order. We hold that such action was well within the Board’s discretion for the reasons set forth in the Board’s decision, 212 N.L.R.B. No. 21, but do not accept as an absolute the contention that objections to the validity of an election must be made within five days after such election.

The order will be enforced. See Rule 17(b).