Serious study of American radio drama of the 1920s and early 1930s is, at best, very limited. Unsung pioneers of the art include: WLW's Fred Smith; Freeman Gosden and Charles Correll (who popularized the dramatic serial); The Eveready Hour creative team (which began with one-act plays but was soon experimenting with hour-long combinations of drama and music on its weekly variety program); the various acting troupes at stations like WLW, WGY, KGO and a number of others, frequently run by women like Helen Schuster Martin and Wilda Wilson Church; early network continuity writers like Henry Fisk Carlton, William Ford Manley and Don Clark; producers and directors like Clarence Menser and Gerald Stopp; and a long list of others who were credited at the time with any number of innovations but who are largely forgotten or undiscussed today. Elizabeth McLeod's 2005 book on Gosden and Correll's early work[20] is a major exception, as is Richard J. Hand's 2006 study of horror radio, which examines some programs from the late 1920s and early 1930s.[21]