Copyright question on use of quotations
<p>Writing a book on history of structural analysis and use extensively secondary sources.</p>
<p>To which extent can I copy long paragraphs of the book while clearly indicating one of the following</p>
<ul>
<li>just cite</li>
<li>write based on or adapted from</li>
</ul>
<p>I do not put in quote long passages.</p>
<p>Can I get by placing a grey background from copied passage</p>
<p>Trying to avoid having to paraphrase</p>

<p>When you are citing a source to back up your statements, you may generally quote a reasonable amount. Under US law, this will be a form of <em><strong>fair use</strong></em> Under the laws of other countries, this <strong>may</strong> be permitted under one or another <em><strong>exception to copyright</strong></em>. The available exceptions and how they work vary from country to country, but reasonable quotes should be allowed in almost every country.</p>
<p>See <a href="https://law.stackexchange.com/questions/32422/is-this-copyright-infringement-is-it-fair-use-what-if-i-dont-make-any-money-o">Is this copyright infringement? Is it fair use? What if I don&#39;t make any money off it?</a></p>
<p>You should:</p>
<ul>
<li>Make it clear what content is quoted, who originally wrote or said it, and when and where it was published;</li>
<li>Quote not more than is needed to support your point.</li>
<li>Not quote in such a way that your work can be used as a substitute for the source work.</li>
</ul>
<p>If you are not making a reference quote, but merely reusing an idea from a source, it is usually better to write the idea in your own words, not closely following the structure or wording of your source.</p>
<p>However, if you are criticizing or commenting on what another author has written, you may (and should) quote enough to show what your comments or critique refers to. The same principles apply as with a reference quote: make what is quoted clear; attribute the source; and quote no more than is reasonable needed for your purpose.</p>
<p>Consider whether you really need to quote &quot;long paragraphs&quot; or can just quote key sentences, perhaps along with paraphrases of the rest.</p>
<p>If at all possible, the parts you quote should be only a small proportion of the source work.</p>

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