The judgment of the district court is affirmed.

We agree with the district court that the escrow instructions signed by the parties constituted a binding obligation ab initio to sell and to buy.

It is our view that until March 4, 1968, the buyers could have terminated the contract by a refusal to approve the “restrictions,” using the reasons they ultimately used. But they did it too late when they disapproved on March 18, 1968.