Complex sentence: Designed under the leadership of Alec Issigonis, more than 1.3 million were manufactured between 1948 and 1972 in three series: the MM (1948), the Series II (1952) and finally the 1000 series (1956).
Split into simpler sentences: Designed under the leadership of Alec Issigonis, more than 1.3 million were manufactured between 1948 and 1972. The Minor was manufactured in three series: the MM (1948), the Series II (1952) and finally the 1000 series (1956).