Is it unethical if we cite a paper with mentioning the publication venue (e.g,. author, "paper title," journal name, year) when quoting or mentioning some idea from it, while we have not even seen the paper in its final published form and what we have read is indeed previous versions of it (e.g., because we got it from the author's homepage, arXiv, etc., which are not copy-editted and may have some differences with the final version)?
If yes, what is the solution? (Having many references without any publication venues and e.g., by mentioning the url of the file we have, makes our paper ugly)