Borland International (1992). "Turbo Vision for C++ User's Guide". Scotts Valey, CA.
The link was suggested by the manual itself (see page 492). After pondering this indexed item deeply and philosophically, we realised that there was no answer! Therefore, applying the rule more honoured in its breach than observance, "Keep it simple", it became obvious that the reference had to be to the object itself, a (*this)!
On a more serious note, TV is not well documented. The manual can only be described as obscure. This is unfortunate as a library's manual is a powerful adjunct. If the manual is unclear, then the benefits from the library will not be fully realised.
One of the objectives of TVPlus, with your support, will be to clarify some of the points the manual tends to present unclearly, or does not mention at all. If you want to record dead parrots (i.e. would be errata), we would be happy to note them here.