Let A=(A_i)_{i in N_0} be a stationary stochastic process in GL(d,R), where GL(d,R) denotes the set of invertible d times d matrices with real entries. Over the past decades an extensive theory has been developed on the asymptotic behaviour of sequences of the form label{abstreq1} (1/n lnA_n....A_0)_{n in N} and label{abstreq2} (1/n lnA_n...A_0 x)_{n in N} with x a vector in R^d. A lot of material is available on conditions ensuring the existence of almost sure limits as well as characterisations of these limits in case of existence. Along these lines, statements of the type of the central limit theorem in classical probability theory have been proved. Satisfactory answers have been given to these questions amongst others by Furstenberg and...