Adding PPA resource into preceed file

[juffinhalli]

Good day!
I actively use opportunities pretseed fillets to automate installation 
of Ubuntu in my organization. However, many packages have become 
obsolete in the stable version(precise), for example xfce4. To solve 
this problem, I use the PPA. And, accordingly, the question - can I use 
the PAP resources during preceed installation? That is, the packets 
listed in the key of "d-i pkgsel / include string" is used directly in 
the PPA resources.

Thank you in advance for your help.