I recently came across the following result:
For any integers $d,r\geq 2$ and $n\geq 4d^{r(d+1)}$, there is a $d$-regular graph on $n$ vertices with girth at least $(d+1)r+1$.
referring to
"P. Erdős and H. Sachs, Reguläre Graphen gegebener Taillenweite mit minimaler Knotenzahl, Wiss. Z. MartinLuther-Univ. Halle-Wittenberg Math.-Natur. Reihe 12 (1963), 251–257."
This paper can be downloaded from https://users.renyi.hu/~p_erdos/1963-16.pdf.
Unfortunately, this was written in German. Would anyone be kind enough to explain it briefly in English? Besides, there are fancy results in the last century written in Russian, Germany, and France, etc. For those that are not translated in English, is there a useful way to read them?
I indeed tried Google translation but turns out to be like the following picture:
Ugh....