Roadside America is mentioned in the following publications:

Fun Along the Road by John Margolies, pp 54-55
Weird Pennsylvania by Matt Lake, p. 153
Road Trip USA (1st Edition) by Jamie Jensen, p. 267
Road Trip USA (3rd Edition) by Jamie Jensen, p. 355
Unique and Unusual Places in the Mid-Atlantic Region by  William N. Hoffman, pp. 141-142
Railroads of Pennsylvania by Lorett Treese, pp. 70-71
Kids Love Pennsylvania, by George and Michele Zavatsky, pp. 128, 178
I'm a Stranger Here Myself, by Bill Bryson, p. 137
An Eccentric Guide to the United States, by James Dale Davidson, pp. 111-113
Country Towns of Pennsylvania, by Marcus Schneck, pp. 123-127
Road Trip America, by Andrew F. Wood, pp. 84-85
Daytrips: Pennsylvania Dutch Country & Philadelphia, by Earl Steinbicker, p. 244
1000 Places to See in the USA and Canada Before You Die, by Patricia Schultz, pp. 231-232