本文目的是要在三維的Dirac-Klein-Gordon方程式建立一個局部存在結果，主要使用固定點論據和null form估計。在第一和第二部分我們做了許多估計，我們希望證明各部份都是有界的。在第三個部分，我們準備針對DKG方程式，證明有局部存在性。我設法找到一個收縮映射T1。在第四個部分, 我們展示關鍵估計的證明。

The purpose of this paper is to establish a local existence result for Dirac-Klein-Gordon equations in the three dimensions, employing a fixed point argument and a null form estimate.
We have made many estimates in first and the second section. We wish each part is bounded.
In the third section, we are ready to prove the local existence for (DKG) equations. I try to find a contraction mapping T1. In the fourth section, we demonstrate the proof of the key estimate.

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