employer sent 797C - approval notice. can I start job?

[mryogik]

My new employer sent me I797C which is an approval notice for H1 petition. 

 

it obviously does not contain I-94. 

 

Should I wait for the employer to receive I797A with I-94 before I start the job?

 

The 797C clearly states - "The above petition and extension of stay has been approved. the foreign worker can work for the petitioner only as detailed in petition and for period authorized......"

It even talks about I94 as if it is attached to the form. But it is not attached as it is just notice.