I assume you mean a citation for a publication in a scholarly journal or book.
You should always cite the actual source that you consulted. If you used a translation, then you cite the translation.
You can optionally include the publication facts of the work being translated if it is a particular book, for example:
Derrida, Jacques. Writing and Difference. Translated by Alan Bass.
Chicago: University of Chicago Press, 1978. Originally published as
L'ecriture et la difference (Paris: Editions du Seuil, 1967).
If the document is translated from inscriptions, or an ancient manuscript naming the work in Sanskrit may be unnecessary, you just cite your source (here is MLA style):
Luckenbill, Daniel David. Ancient Records of Assyria and Babylonia:
Historical records of Assyria, from Sargon to the end. Greenwood
If the work has a specific title, it can be included in translation (here in Chicago style):
Moussa-Mahmoud, Fatma. "A Manuscript Translation of the" Arabian
Nights" in the Beckford Papers." Journal of Arabic Literature (1976):
In most cases, the title of the translated work will itself name the manuscript in question:
Mahesh Yogi, Maharishi. Maharishi Mahesh Yogi on the Bhagavad-Gita: A
new translation and commentary with Sanskrit text, Chapters 1 to 6.
Harmondsworth: Penguin Books, 1969.
In some cases, when dealing with original texts you will need to reference a particular passage or even a specific word or letter. This is not a "citation", but is a "reference" or "textual note." A citation is always to an authority. To reference a part of a text, there are several different conventions:
The main approach is to reference a line number. So, for example, for each of Homer's two books (Iliad and the Odyssey), every line or "verse" has a number. So you can refer to a particular verse by line:
meaning Book 2 (beta), line 143. Multiple lines:
Virgil is the same. Some books have multiple section, for example Horace:
Meaning book 3, poem 2, lines 1-4. See Newcastle University's guidelines for classical references for more information. If you are referring to a work that has multiple mss and no standard delineation, then you must decide on a delineation standard from a particular editor. In cases where readers may not have access to a particular edition, then the best practice is to repeat the passage.
For example, let's take an answer I made to this forum regarding a question on an inscription from the Great Colonnade. In this case the book that is needed is very rare and difficult to obtain, so the text is repeated in the reference:
Yon, Jean-Baptiste (ed). Le programme des Inscriptions grecques et
latines de la Syrie XVII : Palmyre et Palmyrène (vol 1). Inscription
173, line 15, reading: