Just because you can find it for free on the internet, does NOT mean that it is “public domain”.
Sure, it is out there for access by the general public, but “public domain” is a legal concept – with legal consequences!
I was contacted by someone recently who got a bill from Getty’s Images for $800 for using a picture that they copied from the results of a Google search. If it is a Getty’s Image, then they can charge you a fee unless you paid them to use it in the first place. They send out letters every day and pursue payment.
When you search for an image on the internet, most of them come up with “this image may be subject to copyright“. So check before you use it!
You’re first point of call is to check the terms and conditions of the website where you are sourcing pictures. It should stipulate what you can and cannot do with the images sourced from that site.
The same goes with books and other written works.
Essentially, if the author passed on more than 50 years ago, the writing is most likely in the public domain. This is not always true though because in some countries copyright can be renewed and the term of copyright was extended more recently to 70 years after the death of the author in a lot of countries. So you need to know where and when the author died to figure out whether or not a book is still subject to copyright.
For something now in the public domain, you can republish the book and get copyright in the layout (typesetting and appearance) of the way a book is presented, but you won’t get copyright in the actual story or words. You will find a lot of different copies of “Think and Grow Rich” by Napolean Hill out there for just this reason!
I’ve been asked if it is ok to just quote the ISBN of a book in the public domain. The ISBN is associated with the work as published (and identifies the publisher), rather than the content. So for you to quote the ISBN of a different publisher on your website it would in fact be misleading. If you need one, get a new one that identifies you as publisher!
What you should do is ensure that you properly identify the author. If you would like an example of what it is that you want to do, go and have a look at any one of the multitude of books on “The Science of Getting Rich” authored by WD Wattles that are published out there. You will find that each has a different introduction by the person publishing the new edition.
Where can I get public domain books?
There are a number of websites that have a host of public domain publications and explain the origin of those publications. You are safest with books and writings created prior to 1900, however there are many writings published after that date now out of copyright. Gutenberg http://www.gutenberg.org/ is a great example.
Checking whether or not a book is in the public domain depends upon the country in which it was first published, when it was published and when the author died. In the US the law changed from 1 January 1978 so that copyright expired in 2006 unless it was specifically renewed. I am aware that the copyright in Napoleon Hill’s work “Think and Grow Rich” was not renewed, and has therefore expired and is in the public domain in the United States, and according to international conventions, is most likely to be internationally in the public domain. That is only in respect of the original version and not with respect to any of the more recent published editions with introductions by different authors.
Always double check first! Better to be safe, than sorry!