Question about matrices

Hi,
Look at the matrix: Row1: a1,a2,a3,a4; Row2: b1,b2,b3,b4; Row3: c1,c3,c3,c4; Row4: d1,d2,d3,d4; In wich order have i to pass the floats to GL: a1…a3,b1…b3,c1…c3,d1…d3 or
a1,b1,c1,d1,a2,b2,c2,d2,… ?

Thanks
marcio

The last a1, b1…
It is all in the red book that can be downloaded from gamedev.

Downloaded or bought?

Downloaded but it is not the latest edition.