-
1Llyfrgan Solomon, David, 1938-“...United States. Federal Highway Administration...”
Cyhoeddwyd 1964
-
2LlyfrCyhoeddwyd 1968“...United States. Federal Highway Administration...”
-
3LlyfrCyhoeddwyd 1974“...United States. Federal Highway Administration...”
-
4
-
5LlyfrCyhoeddwyd 1972“...United States. Federal Highway Administration...”
-
6LlyfrCyhoeddwyd 1977“...United States. Federal Highway Administration...”
-
7LlyfrCyhoeddwyd 1974“...United States. Federal Highway Administration. Traffic Systems Division...”
-
8Llyfrgan Sack, Ronald L.“...United States. Federal Highway Administration. Offices of Research and Development...”
-
9LlyfrCyhoeddwyd 1972“...United States. Federal Highway Administration...”
-
10Llyfrgan Miklofsky, Haaren A.“...United States. Federal Highway Administration. Offices of Research and Development...”
Cyhoeddwyd 1977
-
11
-
12
-
13LlyfrCyhoeddwyd 1972“...United States. Federal Highway Administration...”
-
14Dogfen y Llywodraeth LlyfrCyhoeddwyd 1976“...United States. Federal Highway Administration. Office of Program and Policy Planning...”
-
15LlyfrCyhoeddwyd 1972“...United States. Federal Highway Administration...”
-
16LlyfrCyhoeddwyd 1994“...United States. Federal Highway Administration...”
-
17
-
18
-
19
-
20LlyfrCyhoeddwyd 1973“...United States. Federal Highway Administration...”