Integral trees with diameters 4, 6 and 8

In this paper, some new families of integral trees with diameters 4, 6 and 8 are given. All these classes are infinite. They are different from those in the existing literature. We also prove that the problem of finding integral trees of diameters 4, 6 and 8 is equivalent to the problem of solving Pell's diophantine equations. The discovery of these integral trees is a new contribution to the search for such trees.