References

McHale M and L A Martin (2017). The performance of surfacing in Scotland - Scottish Inspection Panel Report 2016. Published Project Report PPR821. Crowthorne: TRL Limited.
McHale M and L A Martin (2019). The performance of surfacing in Scotland - Scottish Inspection Panel Report 2018. Published Project Report PPR898. Crowthorne: TRL Limited.
TRIM (2019). Transport Scotland Trunk Road Inspection Manual. Transport Scotland, Buchanan house, Glasgow.