Complex sentence: The popularity of Pip, Squeak & Wilfred was immense; the 16 December 1922 edition of the Daily Mirror reports 100,000 copies of the 1923 "Pip and Squeak Annual" had been sold.
Split into simpler sentences: The popularity of Pip, Squeak & Wilfred was immense. The 16 December 1922 edition of the Daily Mirror reported 100,000 copies of the 1923 "Pip and Squeak Annual" had been sold.