Difference in names on passport for parents

[geekybiz]

Hi
There is slight difference in names of my parents on my passport and their passport. On my passport, my dad's name has "kumar" appended in the end and my mum's name has "devi" appended in the end.

But on their passports, these are not added.

Now, when I am sponsoring their visits (for visitor visa applications) - do I need additional document to prove that these names refer to same person?

If yes, then what exactly needs to be included?

If no, then what name should I put on sponsoring forms (I 134)?

Thanks
Punit Sethi

[immihelp]

Write everything as per what is there in their passports.