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 332 2,021 SH   SOLE   2,021 0 0
58.com Inc ADR COM 31680q104 38,269 921,045 SH   SOLE   921,045 0 0
Advance Auto Parts COM 00751y106 205 1,289 SH   SOLE   1,289 0 0
Altria Group Inc COM 02209S103 4,197 85,174 SH   SOLE   85,174 0 0
American Electric Power COM 025537101 929 15,300 SH   SOLE   15,300 0 0
American Express COM 025816109 130,067 1,397,969 SH   SOLE   1,397,969 0 0
Amgen COM 031162100 258 1,617 SH   SOLE   1,617 0 0
Apple Computer COM 037833100 1,480 13,406 SH   SOLE   13,406 0 0
Applied Materials COM 038222105 341 13,692 SH   SOLE   13,692 0 0
Arch Capital Group Ltd COM g0450a105 638 10,788 SH   SOLE   10,788 0 0
Athenahealth Inc. COM 04685w103 29,140 200,000 SH   SOLE   200,000 0 0
Automatic Data Processing COM 053015103 508 6,091 SH   SOLE   6,091 0 0
BP Amoco PLC ADR COM 055622104 227 5,948 SH   SOLE   5,948 0 0
Bank of America Corp COM 060505104 9,683 541,253 SH   SOLE   541,253 0 0
Bed Bath & Beyond Inc COM 075896100 463 6,075 SH   SOLE   6,075 0 0
Berkshire Hathaway - Cl A COM 084670108 2,220,224 9,824 SH   SOLE   9,824 0 0
Berkshire Hathaway - Cl B COM 084670702 712,040 4,742,188 SH   SOLE   4,742,188 0 0
Bio-Techne Corp COM 09073m104 235 2,540 SH   SOLE   2,540 0 0
Boeing COM 097023105 233 1,790 SH   SOLE   1,790 0 0
Bristol-Myers Squibb COM 110122108 217 3,670 SH   SOLE   3,670 0 0
Brown & Brown Inc. COM 115236101 87,040 2,644,784 SH   SOLE   2,644,784 0 0
CVS Corp. COM 126650100 2,403 24,953 SH   SOLE   24,953 0 0
Cabelas Inc. Cl A COM 126804301 180,626 3,426,782 SH   SOLE   3,426,782 0 0
Canadian Natural Resources COM 136385101 23,711 767,846 SH   SOLE   767,846 0 0
Caterpillar COM 149123101 6,305 68,881 SH   SOLE   68,881 0 0
ChevronTexaco Corp COM 166764100 529 4,716 SH   SOLE   4,716 0 0
Chubb COM 171232101 354 3,422 SH   SOLE   3,422 0 0
Citigroup Inc COM 172967424 326 6,016 SH   SOLE   6,016 0 0
Coca Cola Co. COM 191216100 41,750 988,876 SH   SOLE   988,876 0 0
Colfax Corp COM 194014106 25,857 501,400 SH   SOLE   501,400 0 0
Colgate Palmolive Co. COM 194162103 245 3,548 SH   SOLE   3,548 0 0
Comcast Corp. Spl Cl A COM 20030n200 430 7,474 SH   SOLE   7,474 0 0
ConocoPhillips COM 20825c104 5,458 79,026 SH   SOLE   79,026 0 0
Costco Wholesale Corp COM 22160k105 105,072 741,246 SH   SOLE   741,246 0 0
Cresud SACIFYA Spon ADR Repstg COM 226406106 6,177 612,147 SH   SOLE   612,147 0 0
Ctrip.com International Ltd A COM 22943f100 4,550 100,000 SH   SOLE   100,000 0 0
Danaher Corp. COM 235851102 125,570 1,465,053 SH   SOLE   1,465,053 0 0
Devon Energy Corporation New COM 25179m103 223 3,645 SH   SOLE   3,645 0 0
Diageo PLC Sponsored ADR COM 25243q205 3,677 32,225 SH   SOLE   32,225 0 0
DirectTV COM 25490a309 4,106 47,354 SH   SOLE   47,354 0 0
Discovery Communications Inc S COM 25470F302 28,158 835,044 SH   SOLE   835,044 0 0
Discovery Communications Inc. COM 25468y107 45,195 1,311,904 SH   SOLE   1,311,904 0 0
Disney Walt COM 254687106 5,404 57,374 SH   SOLE   57,374 0 0
Du Pont E I De Nemours & Co. COM 263534109 4,123 55,762 SH   SOLE   55,762 0 0
Duke Energy Corporation -Hldg COM 26441c204 210 2,510 SH   SOLE   2,510 0 0
Ebay Inc COM 278642103 237 4,220 SH   SOLE   4,220 0 0
Edison International COM 281020107 2,809 42,900 SH   SOLE   42,900 0 0
Emcor Group Inc COM 29084q100 74,288 1,669,759 SH   SOLE   1,669,759 0 0
Emerson Electric COM 291011104 318 5,150 SH   SOLE   5,150 0 0
Energizer Holdings Inc COM 29266r108 211 1,644 SH   SOLE   1,644 0 0
Expeditors Int'l of Wash. Inc. COM 302130109 5,436 121,851 SH   SOLE   121,851 0 0
Express Scripts Holding Co. COM 30219g108 415 4,905 SH   SOLE   4,905 0 0
Exxon Mobil Corp COM 30231g103 8,016 86,707 SH   SOLE   86,707 0 0
Fastenal Co COM 311900104 1,142,651 24,025,457 SH   SOLE   24,025,457 0 0
Fifth Third Bancorp COM 316773100 2,333 114,508 SH   SOLE   114,508 0 0
Fossil Group Inc. COM 34988v106 22,148 200,000 SH   SOLE   200,000 0 0
General Electric COM 369604103 5,792 229,211 SH   SOLE   229,211 0 0
General Mills COM 370334104 2,163 40,567 SH   SOLE   40,567 0 0
Goldman Sachs Group Inc COM 38141g104 245,057 1,264,287 SH   SOLE   1,264,287 0 0
Google Inc Cl A COM 38259p508 310,863 585,805 SH   SOLE   585,805 0 0
Google Inc Cl C COM 38259p706 318,160 604,407 SH   SOLE   604,407 0 0
Graham Holdings Co. COM 384637104 2,812 3,256 SH   SOLE   3,256 0 0
Greenlight Capital Re Ltd Cl A COM G4095J109 14,424 441,764 SH   SOLE   441,764 0 0
Groupon Inc. COM 399473107 24,792 3,001,417 SH   SOLE   3,001,417 0 0
HDFC Bank Ltd ADR Repstg 3 Shs COM 40415f101 938 18,473 SH   SOLE   18,473 0 0
Heartland Express COM 422347104 2,730 101,057 SH   SOLE   101,057 0 0
Hexcel Corp COM 428291108 83,098 2,002,840 SH   SOLE   2,002,840 0 0
Home Depot COM 437076102 3,016 28,728 SH   SOLE   28,728 0 0
IAC Interactivecorp COM 44919p300 72,956 1,200,125 SH   SOLE   1,200,125 0 0
IBM COM 459200101 226,386 1,411,033 SH   SOLE   1,411,033 0 0
ITAU Unibanco Holdings S.A. AD COM 465562106 186 14,263 SH   SOLE   14,263 0 0
Idex Corp COM 45167R104 407 5,225 SH   SOLE   5,225 0 0
Idexx Laboratories Corp. COM 45168D104 659,565 4,448,407 SH   SOLE   4,448,407 0 0
Illinois Tool Works COM 452308109 213 2,248 SH   SOLE   2,248 0 0
Innerworkings Inc Com COM 45773y105 7,790 1,000,000 SH   SOLE   1,000,000 0 0
Intel Corp COM 458140100 265 7,311 SH   SOLE   7,311 0 0
Interactive Brokers Group Inc COM 45841n107 50,629 1,736,264 SH   SOLE   1,736,264 0 0
Ishares India 50 ETF COM 464289529 232 7,750 SH   SOLE   7,750 0 0
JP Morgan Chase & Co. COM 46625h100 1,472 23,514 SH   SOLE   23,514 0 0
Jacobs Engineering Group Inc COM 469814107 176,677 3,953,399 SH   SOLE   3,953,399 0 0
Johnson & Johnson COM 478160104 7,942 75,946 SH   SOLE   75,946 0 0
Kinder Morgan Inc. COM 49456b101 407 9,630 SH   SOLE   9,630 0 0
Kraft Foods Group Inc. COM 50076Q106 1,092 17,424 SH   SOLE   17,424 0 0
Lennox International Inc. COM 526107107 1,857 19,533 SH   SOLE   19,533 0 0
Leucadia Nat'l COM 527288104 369 16,471 SH   SOLE   16,471 0 0
Linear Technology Group COM 535678106 6,192 135,795 SH   SOLE   135,795 0 0
Lockheed Martin Corp. COM 539830109 530 2,750 SH   SOLE   2,750 0 0
Lowe's Companies Inc. COM 548661107 696 10,114 SH   SOLE   10,114 0 0
MRC Global Inc. COM 55345k103 12,175 803,615 SH   SOLE   803,615 0 0
Mastercard Inc COM 57636q104 464,436 5,390,387 SH   SOLE   5,390,387 0 0
McDonalds COM 580135101 12,815 136,767 SH   SOLE   136,767 0 0
McGraw Hill COM 580645109 44,966 505,350 SH   SOLE   505,350 0 0
Medtronic Inc COM 585055106 339 4,700 SH   SOLE   4,700 0 0
Merck & Co. COM 58933y105 272 4,784 SH   SOLE   4,784 0 0
Microsoft COM 594918104 2,933 63,149 SH   SOLE   63,149 0 0
Mohawk Industries COM 608190104 439,198 2,826,972 SH   SOLE   2,826,972 0 0
Mondelez International COM 50075n104 2,059 56,680 SH   SOLE   56,680 0 0
Novo Nordisk A/S ADR COM 670100205 3,478 82,192 SH   SOLE   82,192 0 0
O Reilly Automotive Inc COM 67103h107 694,836 3,607,287 SH   SOLE   3,607,287 0 0
Omnicom Group COM 681919106 222,655 2,874,082 SH   SOLE   2,874,082 0 0
Oracle Corp. COM 68389X105 2,819 62,693 SH   SOLE   62,693 0 0
PepsiCo COM 713448108 17,752 187,735 SH   SOLE   187,735 0 0
Perrigo Co PLC COM G97822103 284,119 1,699,683 SH   SOLE   1,699,683 0 0
Pfizer COM 717081103 342 10,967 SH   SOLE   10,967 0 0
Philip Morris Intl Inc. COM 718172109 7,438 91,317 SH   SOLE   91,317 0 0
Phillips 66 COM 718546104 2,832 39,491 SH   SOLE   39,491 0 0
Pioneer Natural Resources Co. COM 723787107 26,043 174,962 SH   SOLE   174,962 0 0
Praxair COM 74005P104 245,102 1,891,801 SH   SOLE   1,891,801 0 0
Precision Castparts Corp COM 740189105 745,033 3,092,962 SH   SOLE   3,092,962 0 0
Price T Rowe Group Inc COM 74144t108 347 4,045 SH   SOLE   4,045 0 0
Primerica Inc COM 74164M108 201,654 3,716,445 SH   SOLE   3,716,445 0 0
Procter & Gamble COM 742718109 14,617 160,473 SH   SOLE   160,473 0 0
Progressive Corp. Ohio COM 743315103 1,753 64,940 SH   SOLE   64,940 0 0
Public Storage Inc. COM 74460d109 461 2,493 SH   SOLE   2,493 0 0
Qihoo 360 Technology Co. ADR COM 74734m109 85,890 1,500,000 SH   SOLE   1,500,000 0 0
Qualcomm Inc COM 747525103 22,468 302,267 SH   SOLE   302,267 0 0
Range Resources Corp COM 75281a109 192,709 3,605,407 SH   SOLE   3,605,407 0 0
Republic Services Inc Cl A COM 760759100 505 12,555 SH   SOLE   12,555 0 0
Resource America Inc - (RESTRI COM 761195205 2,659 294,117 SH   SOLE   294,117 0 0
Resource America Inc Cl A COM 761195205 5,453 603,180 SH   SOLE   603,180 0 0
Robert Half Internat'l COM 770323103 409 7,000 SH   SOLE   7,000 0 0
Roper Industries Inc New COM 776696106 698 4,465 SH   SOLE   4,465 0 0
Royal Bk CDA Montreal Que COM 780087102 3,481 50,400 SH   SOLE   50,400 0 0
Royal Dutch Shell PLC Spon ADR COM 780259206 1,426 21,299 SH   SOLE   21,299 0 0
SEI Investments Co COM 784117103 400 10,000 SH   SOLE   10,000 0 0
Schlumberger Ltd COM 806857108 1,580 18,496 SH   SOLE   18,496 0 0
Sherwin Williams Co. COM 824348106 1,396 5,307 SH   SOLE   5,307 0 0
Sirona Dental Systems Inc COM 82966c103 247,010 2,827,172 SH   SOLE   2,827,172 0 0
Soufun Holdings LTD ADR COM 836034108 14,843 2,008,500 SH   SOLE   2,008,500 0 0
Southwestern Energy Co COM 845467109 109,554 4,014,450 SH   SOLE   4,014,450 0 0
Stericycle Inc. COM 858912108 393 3,000 SH   SOLE   3,000 0 0
Suntrust Banks COM 867914103 1,307 31,203 SH   SOLE   31,203 0 0
TJX Cos - New COM 872540109 1,829,267 26,673,471 SH   SOLE   26,673,471 0 0
TRW Automotive Holdings Corp. COM 87264s106 771 7,500 SH   SOLE   7,500 0 0
Thermo Electron COM 883556102 360 2,873 SH   SOLE   2,873 0 0
Third Point Reinsurance LTD COM g8827u100 14,667 1,012,200 SH   SOLE   1,012,200 0 0
Tiffany & Co COM 886547108 227,817 2,131,921 SH   SOLE   2,131,921 0 0
Trimble Navigation Ltd. COM 896239100 91,201 3,436,368 SH   SOLE   3,436,368 0 0
U.S. Bancorp New - Del. COM 902973304 1,262 28,069 SH   SOLE   28,069 0 0
Union Pacific COM 907818108 12,014 100,846 SH   SOLE   100,846 0 0
United Technologies COM 913017109 215 1,873 SH   SOLE   1,873 0 0
Valeant Pharmaceuticals Intern COM 91911k102 4,913,249 34,331,973 SH   SOLE   34,331,973 0 0
Verisk Analytics Class A COM 92345Y106 3,804 59,385 SH   SOLE   59,385 0 0
Verizon Communications COM 92343v104 320 6,837 SH   SOLE   6,837 0 0
Visa Inc Class A COM 92826C839 225,111 858,546 SH   SOLE   858,546 0 0
WPP PLC New ADR COM 92937a102 296 2,840 SH   SOLE   2,840 0 0
Wal-Mart Stores COM 931142103 190,282 2,215,675 SH   SOLE   2,215,675 0 0
Waters Corp COM 941848103 230,970 2,049,064 SH   SOLE   2,049,064 0 0
Wells Fargo & Co. New COM 949746101 12,857 234,530 SH   SOLE   234,530 0 0
West Pharmaceutical Svcs Inc C COM 955306105 54,540 1,024,416 SH   SOLE   1,024,416 0 0
World Fuel Services Corp COM 981475106 192,366 4,099,001 SH   SOLE   4,099,001 0 0
Yandex NV Shs COM n97284108 52,280 2,910,911 SH   SOLE   2,910,911 0 0
Young Broadcasting Inc Cl A COM 987434107 0 144,865 SH   SOLE   144,865 0 0
Zoetis Inc. COM 98978v103 7,462 173,423 SH   SOLE   173,423 0 0
Constellation Software Inc. COM 21037x100 76,708 257,168 SH   SOLE   257,168 0 0
Jardine Matheson Hldgs (U$.25 COM G50736100 220 3,600 SH   SOLE   3,600 0 0
Ryanair Hldgs PLC Spon ADR COM 783513104 579 8,121 SH   SOLE   8,121 0 0