"direct" quotations and "entire paragraph" quotations

Here is an example using the csquotes package. It defines some new powerful commands for quoting, most notably the commands \enquote, \textquote, \blockquote and \foreignquote.

\foreignquote together with babel allows to define foreign quotes. The correct punctuation will automatically be used.

\textquote and \blockquote allow a citation as optional input, but from your example I guess the following is more what you want.

\documentclass{article}    
\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@article{owens2008,
    author = {Owens},
    title   = "Essay about Value",
    year    = "2008",
    journal = "International Journal of Interesting Stuff",
    volume  = "123",
    number  = "2",
    pages   = "205--319"}
@article{beauvoir1972,
    author  = "Beauvoir, Simone de",
    title   = "About the Gloomieness of landscape",
    year    = "1972",
    journal = "International Journal of Alphabetics",
    volume  = "14",
    number  = "3",
    pages   = "34--359"}
\end{filecontents}
%
\usepackage[round, sort, compress, authoryear]{natbib}
\usepackage[italian,english]{babel}
\usepackage[autostyle]{csquotes}  
%
\begin{document}
Lorem ipsum dolor sit amet.
As \citet[][p.97]{owens2008} stated, \enquote{the value of...}.
Some more lorem ipsum.\\
Some more lorem ipsum.
\citet[][p.365]{beauvoir1972} examined her own past and wrote rather gloomily:
\blockquote{The past is not a peaceful landscape lying there behind me, 
a country in which I can stroll wherever I please, 
and will gradually show me all its secret hills and dates. 
As I was moving forward, so it was crumbling. 
Some more text to make it longer than three lines. 
Maybe it is long enough now.}
Some more lorem ipsum.
Also there is an Italian proverb saying 
\foreignquote{italian}{Chi beve bene dorme bene,chi dorme bene sogna bene}. 
%
\bibliographystyle{plainnat}
\bibliography{\jobname} 
\end{document}

As far as I can tell, your question is really about how to quote material -- either inline, with other text, or as a block quote. The fact that the material to be quoted comes from a specific cited source is peripheral to the issue, I believe.

• To quote a fairly short string -- whether a single word, a few words, or an entire sentence -- inline, you just surround it by the quotation marks that are appropriate for the language and region you're writing for. For example, in US English it's common to surround inline-quoted material with double back-quotes and double (forward) quotes, as in

    she said, ``Hello.''
  

  In UK English, it's more common to use single (back and forward) quotes. In other languages, other quotation mark styles prevail.

  • If there's a chance that your document will get translated in several languages, you may wish to familiarize yourself with the csquotes package and its \enquote command: Depending on the language specified as an option when this package is loaded, the language-specific (and, if applicable, region-specific) inline quotation sytle will be set up for you automatically.

• To typeset longer quoted material, especially if it's longer than a sentence, it's common to use either the quote or quotation environment. The latter is recommended if you're block-quoting more than one paragraph.

  • I should add that the styles of these two environments satisfy US-English typographic conventions but may not be perfect for other typographic systems. Again, the csquotes package can be of service, as it provides the \blockquote command to implement a block-quotation style that's tailored towards your language.