Published $\text {1225}$.
In English:

The Book of Squares

Historical Note

Leonardo Fibonacci relates in the prologue how he was invited to the court of Emperor Frederick $\text {II}$ of Sicily to compete in a mathematical tournament.

He solved all the problems presented to him by Johannes of Palermo.

The problems and their answers were published in Flos.

Some suggest that they were also published in Liber Quadratorum, but it has not been possible to corroborate this.