APA
Transport and Road Research Laboratory. Supplementary Report nr 171UC, . (1975). Probing ahead for tunnels. Crowthorne: Transport and Road Research Laboratory. Supplementary Report nr 171UC.
Chicago
Transport and Road Research Laboratory. Supplementary Report nr 171UC, . 1975. Probing ahead for tunnels. Crowthorne: Transport and Road Research Laboratory. Supplementary Report nr 171UC.
Harvard
Transport and Road Research Laboratory. Supplementary Report nr 171UC, . (1975). Probing ahead for tunnels. Crowthorne: Transport and Road Research Laboratory. Supplementary Report nr 171UC.
MLA
Transport and Road Research Laboratory. Supplementary Report nr 171UC, . Probing ahead for tunnels. Crowthorne: Transport and Road Research Laboratory. Supplementary Report nr 171UC. 1975.