I need to switch images onlcick using JS

Firstly sorry if this seem a dumb question but I am learning javascript so may have messed this up.

I have an image that clickis replaced by nother image in its place.The problem I am trying to worj out is where do i place the second image link.

HTML below

 <div class="col-lg-3">

<img id="pbook" onclick="imageChange" class="imagebooks"  src="images/pink1.jpg" alt="">


 </div>

Javascript incomplete below:

function imageChange (newImage) {

 var secondImage= document.getElementById("pbook");
  secondImage.style.src = newImage;

}

Thank you for your kind help.

I have tried to create a function that when the image is click by the user is switches to another image. Basically the front image of a book that is then clicked on shows thw bck of the book.