Columbia subject headings:
Roads--Environmental aspects--Europe.
Traffic safety and wildlife--Europe.
Wildlife crossings--Europe.
Wildlife habitat improvement--Europe.
Harvard subject headings:
Roads--Environmental aspects--Europe.
Traffic safety and wildlife--Europe.
Wildlife crossings--Europe.
Wildlife habitat improvement--Europe.
Princeton subject headings:
Roads--Environmental aspects--Europe.
Traffic safety and wildlife--Europe.
Wildlife crossings--Europe.
Wildlife habitat improvement--Europe.