Dave,
"The original 60/991,395 ..."
You've got the right idea in the way you've described the relationship. What the applicants have done is filed a US nonprovisional application, US 12/018,217, and an international application, PCT/US08/76962, claiming priority to the earlier filed US provisional application, 60/991,395. The disclosures of the three applications are similiar.
I'll recap because the processes can be confusing. There are at least three ways to get the references you believe relevant considered in the prosecution of the US nonprovisional application.
(1) Within 60 days of the publication of the US 12/018,217 file a 37 CFR 1.99, a 'Third-party submission in published application." See
http://www.uspto.gov/web/offices/pac...e8r7_appxr.pdf.
(2) Trigger the applicants' duty of disclosure by providing to applicants references that you believe are relevent. See
http://www.uspto.gov/web/offices/pac...e8r7_appxr.pdf.
(3) Lodge a protest as to the merits of the application. See
http://www.uspto.gov/web/offices/pac..._e8r5_1900.pdf.
My suggestion as to (2) is that you provide the references, your explanation of why you believe them relevant, and a copy of the US nonprovisional application claims to the attorney and each of the applicants by certified mail. The addresses of the four inventors are available to the public in image file wrapper of the application on the document called the 'Oath or Declaration.' The image file wrapper can be accessed by going to the USPTO website, finding the link to 'Public PAIR', searching by the application number, and finding the above-mentioned document of the 'Image File Wrapper' tab. The pending claims are there as well.
You can then 'check' for good faith by periodically checking the image file wrapper to watch for a responsive filing by the applicant. Should they choose not to identify the reference(s) to the examiner, and the reference be relevant to the claims ultimately allowed the patent can be challenged. The practicioner understands this, and I expect will accordingly act responsibly.
"I am not yet sure whether to used form PTO/SB/08a...."
This form is what the practicioner will likely use to submit references to the USPTO. In your circumstances, it is more important to list the references, cite the relevant sections and explain why you believe them to be relevant to the US nonprovisional rather than be concerned about the form. The USPTO is fairly flexible in dealing with the public genernally, which makes sense because they are, after all, public employees. They will likely cut you slack on formality issues.
Good luck!