Where can I find the source of the Coppersmith method univariate in C with GMP library?

Could someone please tell me where I can find the source code of the Coppersmith method univariate written in C with the GMP library?

to be fair I will explain how I will use it for factoring

reference https://www.academia.edu/48848013/Lepore_Factorization_nr_88

Let's take the example N=1763 of Factorization nr 88 Part I

$P=27*b+1$ ; $p=65-8*b$

$Q=25*a+11$ ; $q=67-8*a$

$p^2=(65-8*b)^2=64*b^2-1040*b+4225$

We find the integer delta $D$ of $x*p+p^2$

$(27*x-1040)^2-4*64*(4225+x)=D^2$

$x=1/729*(28208-sqrt(729*D^2+795691264))$

$795691264=1763*451328$

A partial factorization of $451328$ that is $8$ is the biggest problem with my approach

we replace $D$

$28208-729*x-27*sqrt[(27*x-1040)^2-4*64*(4225+x)]=8*(67-8*a)$

$->$

$64*a^2+55344*a+11964681=729*W$

$55344+729*x=64*y$ $->$ $x=16$

$11964681+729*x=64*y$ $->$ $x=15$

$[64/64*a^2+(((55344+16*729)/64) mod (729))*a+(((11964681+15*729)/64) mod (729))] mod (729) = 0$

$(a^2+318*a+495) mod (729) = 0$

Applying the Coppersmith univariate method

$->$ $a=3$ $->$ $q=43$