It's best not to do this.

If you really meet a serious teacher to check, your proof is fabricated, and you will still be in trouble.

Some students really meet teachers who have to check every quotation. There is one, but none of them works.

How can you guarantee that you won't meet such a teacher? And from a strict point of view, you shouldn't just make it up. It's really ridiculous.

If you can't find the original, don't quote it, find a substitute, or skip this passage. If this is the core content that supports you, it is a very small literature that is so hard to find. In fact, there are risks in theory.

Especially if you're still using your graduation thesis. Although the requirements of undergraduate thesis are far less than those of master's and doctoral thesis, if the requirements of the school are stricter, you will also be in trouble.

Be strict. If this graduation thesis is a master's degree or above, it should be included in the online database. Let's try to sort it out.

Why are you making this up? Can't find the page number, or won't you find it?

Go to Wanfang, VIP and HowNet to download the original text, and you can check the page number. In Wanfang, check the literature and click, there will be relevant information about the publication of the paper, and there should also be a page number range.

Baidu academic search literature, click on the citation, sometimes there will be a page number range.

There are many ways, search more.