. "The British Rail Class 144 Pacer diesel multiple units (DMUs) were built by BREL Derby from 1986 to 1987. A total of 23 units were built, replacing many of the earlier first-generation \"Heritage\" DMUs."@en . "99"^^ . "157"^^ . "British Rail Class 144 Pacer"@en . "23"^^ . . . . .