The advice I give to my students asking this question is that once you keep on finding the same authors, the same theories, the same ideas, the same methods, the same results, you realize that your library of papers in this field has reached saturation.

In truth, your literature review is never complete, as you keep on adding references as you come across them.

However, there is a deadline for the first paper, a deadline for the first chapter, and a deadline for the last chapter, so you have to be content with a less-than-perfect view of the state of the art.

Remember that the main purpose of your literature review is to ensure that no-one has done the work before. You could find, just as you are writing your last chapter, that someone else has beaten you to publication.

In reality, your research interests move on, and you stop following a field of previous interest.

The figures for my own libraries are:

• For general interest reading of a topic, with no immediate plan for research: 10 pdfs
• For finding out the rough nature and boundaries of a field or for investigating plagiarism: 20 pdfs;
• For defining a potential research topic: 30 pdfs;
• For a preliminary review of a field: 100 pdfs;
• For a paper-chapter or a M. thesis: 200 pdfs;
• For a research monograph: 400 pdfs;
• For a PhD: perhaps 1000 pdfs;
• For a textbook: 1500 pdfs

By no means will all the pdfs in a library end up being referenced. It may be just one word that is useful to me, or I may even save a bad paper just to remind me not to download it again!

Dear Julfikar Ali,

I don't think  that you can get a clear answer to this. In simplistic way, you have to understand why you are undertaking a literature review irrespective of the subject of study ( in this case business or social science). So you will realize that it is to understand the existing knowledge on the subject of study and then search available theories, concepts and previous studies. When you realized that you have sufficient knowledge on those three areas of your subject of study, your question have been answered.

The advice I give to my students asking this question is that once you keep on finding the same authors, the same theories, the same ideas, the same methods, the same results, you realize that your library of papers in this field has reached saturation.

In truth, your literature review is never complete, as you keep on adding references as you come across them.

However, there is a deadline for the first paper, a deadline for the first chapter, and a deadline for the last chapter, so you have to be content with a less-than-perfect view of the state of the art.

Remember that the main purpose of your literature review is to ensure that no-one has done the work before. You could find, just as you are writing your last chapter, that someone else has beaten you to publication.

In reality, your research interests move on, and you stop following a field of previous interest.

The figures for my own libraries are:

• For general interest reading of a topic, with no immediate plan for research: 10 pdfs
• For finding out the rough nature and boundaries of a field or for investigating plagiarism: 20 pdfs;
• For defining a potential research topic: 30 pdfs;
• For a preliminary review of a field: 100 pdfs;
• For a paper-chapter or a M. thesis: 200 pdfs;
• For a research monograph: 400 pdfs;
• For a PhD: perhaps 1000 pdfs;
• For a textbook: 1500 pdfs

By no means will all the pdfs in a library end up being referenced. It may be just one word that is useful to me, or I may even save a bad paper just to remind me not to download it again!

thanks  a lot,sir,#Ian Kennedy  and#Pannilage Upali

This is an important question to ask yourself. As well as helping you to write a good literature review, fully understanding the need for such work is what allows you to know you're on-track, why what you're doing is worthwhile, and that you do have a contribution to make. In other words, the literature review is integral to the whole thesis; it is not just a routine step taken to fulfil formal requirements.

You need a good literature review because it:

demonstrates that you know the field. This means more than reporting what you've read and understood. Instead, you need to read it critically and to write in such a way that shows you have a feel for the area; you know what the most important issues are and their relevance to your work, you know the controversies, you know what's neglected, you have the anticipation of where it's being taken. All this would allow you to map the field and position your research within the context.

justifies the reason for your research. This is closely connected with demonstrating that you know the field. It is the knowledge of your field which allows you to identify the gap which your research could fill. However, it is not enough to find a gap. You have also to be able to convince your reader that what you are doing is important and needs to be done.

 https://www.uq.edu.au/student-services/phdwriting/phfaq23.html

It depends on your plan and purpose of review which you must complete according to your general aim as prof. Ian Kennedy mentioned comprehensively in his answer.

Regards

SM Najim

personally, I recommend Ian's list"

For general interest reading of a topic, with no immediate plan for research: 10 pdfs

For finding out the rough nature and boundaries of a field or for investigating plagiarism: 20 pdfs;

For defining a potential research topic: 30 pdfs;

For a preliminary review of a field: 100 pdfs;

For a paper-chapter or a M. thesis: 200 pdfs;

For a research monograph: 400 pdfs;

For a PhD: perhaps 1000 pdfs;

For a textbook: 1500 pdfs