Hi GArik,

I review the following original sentence and think a while.
> specifying the parent of that commit object to be whatever SHA-1 value the reference in HEAD points to.

Yes the sentence is correct as it is. The "reference" here is just what I mean the "head commit". It is just somehow too brief to understand. 

But I still would like to explain what I mean "working branch" and "head commit" here.
 - **working branch** : The branch you check out. Who's head is referenced in HEAD file. So we may say that working branch is the HEAD branch.
 - **head commit** : The last commit in the branch. Who's SHA1 is referenced in the corresponding head file.

I admit "working branch" and "head commit" are not often used terms and may make confuse.