van Swaay, C.A.M., Nowicki, P., Settele, J. & van Strien, A.J. (2008) Butterfly monitoring in Europe: methods, applications and perspectives. Biodiversity and Conservation, 17, 3455-3469.
Transect counts
van Swaay, C.A.M., Nowicki, P., Settele, J. & van Strien, A.J. (2008) Butterfly monitoring in Europe: methods, applications and perspectives. Biodiversity and Conservation, 17, 3455-3469.
Harker, R.J. & Shreeve, T.G. (2008) How accurate are single site transect data for monitoring butterfly trends? Spatial and temporal issues identified in monitoring Lasiommata megera. Journal of Insect Conservation, 12, 125-133.