The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
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COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3M Company COM 88579y101 333 2,021 SH   SOLE   2,021 0 0
58.com Inc ADR COM 31680q104 76,456 1,445,845 SH   SOLE   1,445,845 0 0
Altria Group Inc COM 02209S103 3,860 77,174 SH   SOLE   77,174 0 0
American Electric Power COM 025537101 871 15,485 SH   SOLE   15,485 0 0
American Express COM 025816109 109,177 1,397,551 SH   SOLE   1,394,256 0 3,295
Amgen COM 031162100 258 1,617 SH   SOLE   1,617 0 0
Apple Computer COM 037833100 1,668 13,406 SH   SOLE   13,406 0 0
Applied Materials COM 038222105 309 13,692 SH   SOLE   13,692 0 0
Arch Capital Group Ltd COM g0450a105 658 10,688 SH   SOLE   10,688 0 0
Athenahealth Inc. COM 04685w103 23,878 200,000 SH   SOLE   200,000 0 0
Automatic Data Processing COM 053015103 522 6,091 SH   SOLE   6,091 0 0
BP Amoco PLC ADR COM 055622104 233 5,948 SH   SOLE   5,948 0 0
Bank of America Corp COM 060505104 8,325 540,953 SH   SOLE   540,953 0 0
Bed Bath & Beyond Inc COM 075896100 466 6,075 SH   SOLE   6,075 0 0
Berkshire Hathaway - Cl A COM 084670108 2,065,598 9,497 SH   SOLE   9,492 0 5
Berkshire Hathaway - Cl B COM 084670702 685,894 4,752,589 SH   SOLE   4,745,825 0 6,764
Bio-Techne Corp COM 09073m104 255 2,540 SH   SOLE   2,540 0 0
Blackrock Inc Cl A COM 09247x101 201 550 SH   SOLE   550 0 0
Boeing COM 097023105 269 1,790 SH   SOLE   1,790 0 0
Bristol-Myers Squibb COM 110122108 237 3,670 SH   SOLE   3,670 0 0
Brown & Brown Inc. COM 115236101 87,012 2,627,964 SH   SOLE   2,623,442 0 4,522
CVS Corp. COM 126650100 2,575 24,953 SH   SOLE   24,953 0 0
Cabelas Inc. Cl A COM 126804301 191,560 3,421,943 SH   SOLE   3,418,700 0 3,243
Canadian Natural Resources COM 136385101 23,505 765,389 SH   SOLE   764,677 0 712
Caterpillar COM 149123101 5,513 68,881 SH   SOLE   68,861 0 20
ChevronTexaco Corp COM 166764100 495 4,716 SH   SOLE   4,716 0 0
Chubb COM 171232101 346 3,422 SH   SOLE   3,422 0 0
Citigroup Inc COM 172967424 310 6,016 SH   SOLE   6,016 0 0
Coca Cola Co. COM 191216100 35,507 875,640 SH   SOLE   875,376 0 264
Cognizant Technology Solutions COM 192446102 205 3,279 SH   SOLE   3,279 0 0
Colfax Corp COM 194014106 23,932 501,400 SH   SOLE   501,400 0 0
Colgate Palmolive Co. COM 194162103 246 3,548 SH   SOLE   3,548 0 0
Comcast Corp. Spl Cl A COM 20030n200 419 7,474 SH   SOLE   7,474 0 0
ConocoPhillips COM 20825c104 4,920 79,026 SH   SOLE   79,026 0 0
Costco Wholesale Corp COM 22160k105 112,250 740,950 SH   SOLE   738,872 0 2,078
Cresud SACIFYA Spon ADR Repstg COM 226406106 8,423 612,147 SH   SOLE   612,147 0 0
Ctrip.com International Ltd A COM 22943f100 5,862 100,000 SH   SOLE   100,000 0 0
Danaher Corp. COM 235851102 122,621 1,444,302 SH   SOLE   1,443,816 0 486
Devon Energy Corporation New COM 25179m103 201 3,340 SH   SOLE   3,340 0 0
Diageo PLC Sponsored ADR COM 25243q205 3,563 32,225 SH   SOLE   32,225 0 0
DirectTV COM 25490a309 3,913 45,977 SH   SOLE   45,977 0 0
Discovery Communications Inc. COM 25468y107 52,293 1,700,044 SH   SOLE   1,700,044 0 0
Disney Walt COM 254687106 6,018 57,374 SH   SOLE   57,374 0 0
Du Pont E I De Nemours & Co. COM 263534109 3,985 55,762 SH   SOLE   55,762 0 0
Duke Energy Corporation -Hldg COM 26441c204 203 2,640 SH   SOLE   2,640 0 0
Ebay Inc COM 278642103 243 4,220 SH   SOLE   4,220 0 0
Edison International COM 281020107 2,680 42,900 SH   SOLE   42,900 0 0
Emcor Group Inc COM 29084q100 77,510 1,667,961 SH   SOLE   1,666,075 0 1,886
Emerson Electric COM 291011104 285 5,035 SH   SOLE   5,035 0 0
Energizer Holdings Inc COM 29266r108 217 1,571 SH   SOLE   1,571 0 0
Expeditors Int'l of Wash. Inc. COM 302130109 5,684 117,967 SH   SOLE   117,967 0 0
Express Scripts Holding Co. COM 30219g108 426 4,905 SH   SOLE   4,905 0 0
Exxon Mobil Corp COM 30231g103 7,354 86,522 SH   SOLE   86,490 0 32
Fastenal Co COM 311900104 992,899 23,962,800 SH   SOLE   23,891,895 0 70,905
Fifth Third Bancorp COM 316773100 2,158 114,508 SH   SOLE   114,508 0 0
General Electric COM 369604103 5,678 228,867 SH   SOLE   228,798 0 69
General Mills COM 370334104 1,164 20,567 SH   SOLE   20,567 0 0
Goldman Sachs Group Inc COM 38141g104 237,189 1,261,846 SH   SOLE   1,259,637 0 2,209
Google Inc Cl A COM 38259p508 322,624 581,618 SH   SOLE   581,102 0 516
Google Inc Cl C COM 38259p706 330,674 603,420 SH   SOLE   602,784 0 636
Graham Holdings Co. COM 384637104 3,418 3,256 SH   SOLE   3,256 0 0
Greenlight Capital Re Ltd Cl A COM G4095J109 14,048 441,764 SH   SOLE   441,764 0 0
Groupon Inc. COM 399473107 21,640 3,001,417 SH   SOLE   3,001,417 0 0
HDFC Bank Ltd ADR Repstg 3 Shs COM 40415f101 1,083 18,393 SH   SOLE   18,393 0 0
Heartland Express COM 422347104 2,401 101,057 SH   SOLE   101,057 0 0
Hexcel Corp COM 428291108 102,986 2,002,840 SH   SOLE   2,002,840 0 0
Home Depot COM 437076102 3,264 28,728 SH   SOLE   28,728 0 0
IAC Interactivecorp COM 44919p300 80,972 1,200,115 SH   SOLE   1,200,115 0 0
IBM COM 459200101 224,884 1,401,148 SH   SOLE   1,399,187 0 1,961
ITAU Unibanco Holdings S.A. AD COM 465562106 158 14,263 SH   SOLE   14,263 0 0
Idex Corp COM 45167R104 396 5,225 SH   SOLE   5,225 0 0
Idexx Laboratories Corp. COM 45168D104 629,993 4,078,152 SH   SOLE   4,075,060 0 3,092
Innerworkings Inc Com COM 45773y105 6,720 1,000,000 SH   SOLE   1,000,000 0 0
Intel Corp COM 458140100 229 7,311 SH   SOLE   7,311 0 0
Interactive Brokers Group Inc COM 45841n107 59,068 1,736,264 SH   SOLE   1,736,264 0 0
Ishares India 50 ETF COM 464289529 241 7,674 SH   SOLE   7,674 0 0
JP Morgan Chase & Co. COM 46625h100 1,424 23,514 SH   SOLE   23,514 0 0
Jacobs Engineering Group Inc COM 469814107 180,017 3,986,209 SH   SOLE   3,981,811 0 4,398
Johnson & Johnson COM 478160104 7,639 75,937 SH   SOLE   75,937 0 0
Kinder Morgan Inc. COM 49456b101 405 9,630 SH   SOLE   9,630 0 0
Kraft Foods Group Inc. COM 50076Q106 1,518 17,424 SH   SOLE   17,424 0 0
LKQ Corp. COM 501889208 6,390 250,000 SH   SOLE   250,000 0 0
Lennox International Inc. COM 526107107 2,182 19,533 SH   SOLE   19,533 0 0
Leucadia Nat'l COM 527288104 367 16,471 SH   SOLE   16,471 0 0
Linear Technology Group COM 535678106 6,066 129,607 SH   SOLE   129,097 0 510
Lockheed Martin Corp. COM 539830109 558 2,750 SH   SOLE   2,750 0 0
Lowe's Companies Inc. COM 548661107 752 10,114 SH   SOLE   10,114 0 0
MRC Global Inc. COM 55345k103 48,561 4,097,935 SH   SOLE   4,097,935 0 0
Makemytrip Ltd COM v5633w109 6,588 300,000 SH   SOLE   300,000 0 0
Mastercard Inc COM 57636q104 466,094 5,395,235 SH   SOLE   5,392,202 0 3,033
McDonalds COM 580135101 13,327 136,767 SH   SOLE   136,767 0 0
McGraw Hill COM 580645109 52,097 503,840 SH   SOLE   503,840 0 0
Medtronic PLC COM G5960l103 381 4,880 SH   SOLE   4,880 0 0
Merck & Co. COM 58933y105 275 4,784 SH   SOLE   4,784 0 0
Microsoft COM 594918104 2,567 63,149 SH   SOLE   63,149 0 0
Mohawk Industries COM 608190104 518,903 2,793,558 SH   SOLE   2,791,046 0 2,512
Mondelez International COM 50075n104 2,046 56,680 SH   SOLE   56,680 0 0
Monsanto Co COM 61166w101 370 3,292 SH   SOLE   3,292 0 0
Novo Nordisk A/S ADR COM 670100205 4,381 82,050 SH   SOLE   82,050 0 0
O Reilly Automotive Inc COM 67103h107 776,419 3,590,544 SH   SOLE   3,587,177 0 3,367
Omnicom Group COM 681919106 221,107 2,835,429 SH   SOLE   2,834,675 0 754
PepsiCo COM 713448108 17,951 187,735 SH   SOLE   187,735 0 0
Perrigo Co PLC COM G97822103 281,222 1,698,713 SH   SOLE   1,697,691 0 1,022
Pfizer COM 717081103 382 10,967 SH   SOLE   10,967 0 0
Philip Morris Intl Inc. COM 718172109 6,879 91,317 SH   SOLE   91,317 0 0
Phillips 66 COM 718546104 3,104 39,491 SH   SOLE   39,491 0 0
Pioneer Natural Resources Co. COM 723787107 646 3,952 SH   SOLE   3,952 0 0
Praxair COM 74005P104 228,290 1,890,753 SH   SOLE   1,889,751 0 1,002
Precision Castparts Corp COM 740189105 740,803 3,527,635 SH   SOLE   3,523,568 0 4,067
Price T Rowe Group Inc COM 74144t108 328 4,045 SH   SOLE   4,045 0 0
Primerica Inc COM 74164M108 184,256 3,619,968 SH   SOLE   3,619,968 0 0
Procter & Gamble COM 742718109 13,132 160,264 SH   SOLE   160,264 0 0
Progressive Corp. Ohio COM 743315103 1,766 64,940 SH   SOLE   64,940 0 0
Public Storage Inc. COM 74460d109 491 2,493 SH   SOLE   2,493 0 0
Qihoo 360 Technology Co. ADR COM 74734m109 76,800 1,500,000 SH   SOLE   1,500,000 0 0
Qualcomm Inc COM 747525103 20,959 302,267 SH   SOLE   302,267 0 0
Range Resources Corp COM 75281a109 208,441 4,005,407 SH   SOLE   4,005,407 0 0
Republic Services Inc Cl A COM 760759100 509 12,555 SH   SOLE   12,436 0 119
Resource America Inc - (RESTRI COM 761195205 2,676 294,117 SH   SOLE   294,117 0 0
Resource America Inc Cl A COM 761195205 5,489 603,180 SH   SOLE   603,180 0 0
Robert Half Internat'l COM 770323103 424 7,000 SH   SOLE   7,000 0 0
Roper Industries Inc New COM 776696106 768 4,465 SH   SOLE   4,465 0 0
Royal Bk CDA Montreal Que COM 780087102 3,042 50,400 SH   SOLE   50,400 0 0
Royal Dutch Shell PLC Spon ADR COM 780259206 1,270 21,299 SH   SOLE   21,299 0 0
SEI Investments Co COM 784117103 441 10,000 SH   SOLE   10,000 0 0
Salix Pharmaceuticals Ltd COM 795435106 3,456 20,000 SH   SOLE   20,000 0 0
Schlumberger Ltd COM 806857108 3,370 40,386 SH   SOLE   40,386 0 0
Sherwin Williams Co. COM 824348106 1,510 5,307 SH   SOLE   5,307 0 0
Sirona Dental Systems Inc COM 82966c103 254,420 2,827,202 SH   SOLE   2,824,876 0 2,326
Soufun Holdings LTD ADR COM 836034108 12,051 2,008,500 SH   SOLE   2,008,500 0 0
Southwestern Energy Co COM 845467109 93,095 4,014,450 SH   SOLE   4,014,450 0 0
Stericycle Inc. COM 858912108 421 3,000 SH   SOLE   3,000 0 0
Suntrust Banks COM 867914103 1,282 31,203 SH   SOLE   31,203 0 0
TJX Cos - New COM 872540109 1,847,988 26,380,983 SH   SOLE   26,356,445 0 24,538
TRW Automotive Holdings Corp. COM 87264s106 786 7,500 SH   SOLE   7,500 0 0
Thermo Electron COM 883556102 386 2,873 SH   SOLE   2,873 0 0
Third Point Reinsurance LTD COM g8827u100 14,323 1,012,200 SH   SOLE   1,012,200 0 0
Tiffany & Co COM 886547108 188,187 2,138,248 SH   SOLE   2,136,251 0 1,997
Trimble Navigation Ltd. COM 896239100 86,469 3,431,299 SH   SOLE   3,425,541 0 5,758
U.S. Bancorp New - Del. COM 902973304 1,135 25,999 SH   SOLE   25,999 0 0
Union Pacific COM 907818108 10,923 100,846 SH   SOLE   100,846 0 0
United Technologies COM 913017109 220 1,873 SH   SOLE   1,873 0 0
Valeant Pharmaceuticals Intern COM 91911k102 6,770,832 34,089,378 SH   SOLE   34,051,579 0 37,799
Verisk Analytics Class A COM 92345Y106 4,229 59,236 SH   SOLE   56,586 0 2,650
Verizon Communications COM 92343v104 342 7,042 SH   SOLE   7,042 0 0
Visa Inc Class A COM 92826C839 224,498 3,432,160 SH   SOLE   3,428,312 0 3,848
WPP PLC New ADR COM 92937a102 323 2,840 SH   SOLE   2,840 0 0
Wal-Mart Stores COM 931142103 181,413 2,205,630 SH   SOLE   2,202,550 0 3,080
Waters Corp COM 941848103 254,765 2,049,264 SH   SOLE   2,047,035 0 2,229
Wells Fargo & Co. New COM 949746101 12,754 234,445 SH   SOLE   234,445 0 0
West Pharmaceutical Svcs Inc C COM 955306105 61,544 1,022,153 SH   SOLE   1,020,379 0 1,774
Yandex NV Shs COM n97284108 59,791 3,942,693 SH   SOLE   3,942,693 0 0
Young Broadcasting Inc Cl A COM 987434107 0 144,865 SH   SOLE   144,865 0 0
Zoetis Inc. COM 98978v103 6,478 139,936 SH   SOLE   139,531 0 405
Constellation Software Inc. COM 21037x100 88,903 257,168 SH   SOLE   257,168 0 0
Jardine Matheson Hldgs (U$.25 COM G50736100 227 3,600 SH   SOLE   3,600 0 0
Ryanair Hldgs PLC Spon ADR COM 783513104 542 8,121 SH   SOLE   8,121 0 0