| Advertisement--"DigiTrak" Drill Head Monitor Straightline Manufacturing, Inc. |
| Advertisement--Radiodetection RD400SL Information, Radiodetection Corporation (Ridgewood, NJ) c/o Telco Sales, Inc., Elkhorn Wisconsin. |
| Advertising Brochure--"SpotDtek" Pipe and Cable Locator (No. 776-16/292) McLaughlin Boring Systems, Greenville, South Carolina. |
| Advertising Brochure--"A New Generation of Machines for the `90`s" (No. 502/991), McLaughlin Boring Systems, Greenville, South Carolina. |
| Advertising Brochure--"Micro-Computerized Pipe Locator Maintenance Manual", Takachiho Sangyo Co., Ltd., Minato-Ku, Tokyo. |
| Advertising Brochure--"Micro-Computerized Pipe Locator Fundamental Principles & Features", Takachiho Sangyo Co., Ltd., Minato, Tokyo. |
| Advertising Brochure--"Push 'N Mole Pipe Pusher McL-1200", (No. 776-15/292), McLaughlin Boring Systems, Greenville, South Carolina. |
| Advertising Brochure--"SpotDtek II Pipe & Cable Locator", (No. 776-16/595), McLaughlin Boring Systems, Greenville, South Carolina. |
| Advertisement--"Surfer for Windows", Golden Software, Inc., Golden, Colorado. |
| Booklet--Instructions for Manually Ploting a Bore, pp. 18-21, using Ditch Witch. |
| Advertising Brochure--"SpotDtek II Bore Location System", (No. 495-18/495), McLaughlin Boring Systems, Greenville, South Carolina. |
| Booklet--"The Steerable System", Smith International, Houston, Texas. |
| Advertisement Brochure--"Maxibor Software", Reflex Instrument, AB, Vallentuna, Sweden. |
| Booklet--"Reflex Maxibor Borehole Survey System", Reflex Instrument, AB, Vallentuna, Sweden. |
| Brochure--No-Dig International, pp. 5-8, Dec. 1995. |
| Brochure--"Pipe Hawk", Emrad Limited, Guildford, Gu2 5YH. |
| Brochure--"ABEM GEOMAC III, Rugged, handheld MS-DOS field computer", ABEM AB Bromma, Sweden, 1991. |
| Brochure--Reflex Maxibor the Vital Swedish Link Between England and France, Reflex Instrument AB, Vallentuna, Sweden. |
| Advertisement--"All Holes Deviate", Reflex Instrument AB, Vallentuna, Sweden. |
| DigiTrack Training Manual, Digital Control Incorporated Oct. 1995 Edition. |